Research on Construction of Suzhou’s Historical Architectural Heritage Corridors and Cultural Relics-Themed Trails Based on Current Effective Conductance (CEC) Model

Abstract

As the cradle of Jiangnan culture, Suzhou is home to a dense concentration of historical architectural heritage that is currently facing existential threats from rapid urbanization. This study aims to develop a spatial heritage corridor network for conservation and sustainable utilization. Using kernel density estimation, this study identifies 15 kernel density groups, along with the Analytic Hierarchy Process (AHP), to pinpoint clusters of historical architectural heritage and assess the involved resistance factors. Current Effective Conductance (CEC) theory is further applied to model spatial flow relationships among heritage nodes, leading to the delineation of 27 heritage corridors and revealing a spatial structure characterized by one primary core, one secondary core, and multiple peripheral zones. Based on 15 source points, six cultural relics-themed routes are proposed—three land-based and three waterfront routes—connecting historical sites, towns, and ecological areas. The study further recommends a resource management strategy centered on departmental collaboration, digital integration, and community co-governance. By integrating historical architectural types, settlement forms, and ecological patterns, the research builds a multi-scale narrative and experience system that addresses fragmentation while improving coordination and sustainability. This framework delivers practical advice on heritage conservation and cultural tourism development in Suzhou and the broader Jiangnan region.

1. Introduction

Cultural heritage, as the carrier of civilization, holds the history, genes, and bloodlines of a nation. As a key cradle of Chinese civilization, the Jiangnan region has given rise to many historic cities and cultural treasures, such as West Lake in Hangzhou, classical gardens, and ancient towns, and it has also become an essential part of the collective memory of the Chinese nation [1].

Among cities in Jiangnan in China, Suzhou is a typical example of studying historical architectural conservation. As the only Grand Canal city nominated for World Heritage status as a historic city [2], it exemplifies the spatial, social, and aesthetic characteristics of Jiangnan culture. Originating from Wu culture, Suzhou has developed a distinct architectural style, cultural logic, and social structure that differ from those of northern cities in China [3]. Suzhou’s historical architectural heritage, listed at various cultural relics conservation units levels, boasts pagodas, temples, guild halls, gardens, residences, and bridges. These structures document the city’s urban evolution and reflect core aspects of traditional Chinese culture, such as kinship systems, social hierarchy, and aesthetic principles. Under globalization, Suzhou’s architectural heritage has gained symbolic value internationally, and its characteristic waterscape imagery (small bridges, flowing water, white walls, and black tiles) has emerged as a powerful cultural icon of China [4,5,6].

Recently, with advancements in preserving heritage and revitalizing urban areas, cultural routes and heritage corridors have become essential tools to link cultural sites and promote cultural tourism growth [7]. In May 2023, China’s State Administration of Cultural Heritage and other agencies issued the Notice on the Construction of Chinese Cultural relics-themed routes, promoting the linkage and coordinated display of cultural relics. However, in Suzhou, the two systems have developed separately. Themed cultural routes remain at a conceptual stage, lacking spatial clarity and structural systems. Heritage corridors, while spatially organized, lack thematic depth and cultural tourism engagement, resulting in a mismatch of content and form. This structural–functional disjunction hinders resource integration and narrative consistency [8].

This study identifies significant challenges related to the distribution of historical and cultural resources, the intensity of tourism development, and the spatial arrangement across ancient Suzhou and its surrounding districts. The specific challenges are as follows.

In Suzhou, the historical architectural heritage is concentrated in the ancient city, on the outskirts of districts and counties: At present, the historical architectural heritage in the ancient city of Suzhou has received relatively concentrated attention and resources. Although the subordinate districts and counties such as Wujiang and Xiangcheng also have rich historical architectural resources, they are mostly marginalized in the overall cultural route, resulting in an unbalanced development of urban heritage tourism.

The fragmentation and disconnection of heritage routes are serious. Due to the barriers of administrative divisions, the transfer of development centers, and the inconsistent pace of historical block renewal, Suzhou’s existing cultural relics tourism routes lack systematic linkage, resulting in a fragmented pattern of independent management and scattered routes, which seriously restricts the continuity of cultural narrative and tourist experience.

Misalignment exists between cultural tourism themes and spatial structures. Currently, many themed cultural relics routes in Suzhou, such as Jiangnan Garden Tour and Wu Culture Exploration Route, have strong cultural recognition, but have not been effectively located on feasible heritage corridors at the spatial level. The embarrassing lack of pathways has affected the route’s feasibility and sustainability.

In order to cope with the above problems, this paper adopts the CEC model to resolve the following three core problems:

(1) Building a historical architectural heritage corridor system with cultural logic and spatial accessibility, breaking through the planning inertia of traditional administrative boundaries and attraction clusters, and realizing cross-district linkage and territory-wide connection.

(2) Establishing cultural relics-themed trails aligned with heritage corridors so as to integrate cultural narratives and tourist experiences into spatial routes. This involves defining route types—such as pilgrimage, ecological, or urban–rural paths—based on heritage categories and visitor behaviors.

(3) Managing the relationships between cultural resources, ecological elements, and urban structure to balance heritage conservation, tourism, and urban renewal. A phased management plan should include pre-assessment, implementation monitoring, and post-maintenance to ensure adaptive governance.

This study addresses the gap between Suzhou’s cultural routes and heritage corridors by introducing the CEC model to guide spatial analysis and integration. It aims to enhance the continuity and interpretability of architectural heritage by considering cultural value, ecological patterns, and urban transformation, so as to provide a replicable experience and strategy for Suzhou and other similar historical and cultural cities.

2. Research Overview

2.1. Research on the Conservation of Historical Architecture

In recent years, we have witnessed significant advancements in research on the conservation of historical architecture, which mainly focuses on building restoration technology, historical value assessment, conservation policies, and multidisciplinary cross-conservation methods. Research in restoration technology focuses on choosing the right materials and building methods to preserve both the appearance and structural integrity of historical architecture [9,10]. Especially in the conservation of wooden structures, scholars have proposed the principle of “Living Heritage Conservation”, which means that, as a material entity, heritage needs to reflect both material and historical continuity of lifestyles, production methods, social organization forms, beliefs, customs and rituals during the restoration process, so as to deepen the understanding of its living nature [11]. The historical value assessment has gradually expanded from considering only the physical characteristics of the building to a comprehensive assessment of multiple dimensions incorporating culture, history, and society. Domestic and foreign researchers have constructed a quantitative assessment model and combined it with a multidisciplinary approach to more comprehensively reveal the deep-seated value of architectural heritage [12,13,14]. In terms of conservation policies, the implementation of the Cultural Relics Conservation Law and the introduction of local regulations have legalized the conservation of historical architecture. The improvement of the relevant legal system provides a solid legal guarantee for architectural conservation [15,16]. At the same time, the application of digital technology, especially 3D scanning, virtual reality (VR), and augmented reality (AR) technologies, has promoted the digital modeling and virtual reconstruction of historical architecture, providing new methods for restoration and conservation [17,18,19].

Nevertheless, the majority of existing studies tend to focus on protecting individual structures or isolated locations, with little attention given to the broader context of historical architecture communities and regional heritage systems. From the perspective of heritage conservation, heritage corridors surpass the limitations of traditional single-architecture conservation, incorporate scattered historical architecture resources into an overall framework, and enhance the systematic nature and continuity of heritage resources by establishing a multi-dimensional connection between culture, history and ecology [20]. This not only contributes to the cultural value and social identity of heritage, but also provides a more scientific, long-term strategy for safeguarding historical structures. From the perspective of geographical planning, heritage corridors provide new ideas for regional spatial planning. By analyzing the spatial relationship between historical architecture and the surrounding environment, heritage corridors can optimize regional land use, coordinate the contradiction between cultural heritage conservation and urban development, and promote the organic integration of historical architecture with natural landscapes and urban functions, thereby achieving a reasonable layout and efficient use of regional space [21,22]. From an architectural perspective, studying heritage corridors offers a novel approach to preserving and repurposing historic architecture. By placing building units in a larger cultural landscape system, architects can better understand the interactive relationship between buildings and the environment, thereby giving them new functions and meanings while protecting historical architecture, and promoting the organic combination of traditional buildings and modern life [23].

In summary, heritage corridor research can not only effectively integrate scattered historical architecture resources, but also provides a scientific basis and practical path for the overall conservation and regional development of historical architecture from the perspective of heritage conservation, geographical planning, and architecture, which has important theoretical value and practical significance.

2.2. Research on the Heritage Corridor in Suzhou

Heritage corridors have gradually emerged as an important way of integrating scattered heritage resources and building a systematic conservation network in heritage conservation research at home and abroad. At present, relevant research mainly focuses on the spatial organization and system construction of various types of cultural heritage, covering cultural heritage along the Beijing–Hangzhou Grand Canal, industrial heritage, railway heritage, traditional villages, red heritage resources (Red heritage resource: In the Chinese context, red heritage resources refer to cultural heritage associated with the revolutionary history led by the Communist Party of China during the New Democratic Revolution period (1921–1949).) and other typical types of heritage [24,25,26,27]. These studies explore the spatiotemporal evolution characteristics of their historical value, the distribution patterns of cultural resources, and suitability evaluation methods [28,29]. On this basis, researchers have further constructed a potential heritage corridor network.

In terms of methodological systems, heritage corridor research has adopted a range of spatial analysis techniques and models [30,31,32]. The Minimum Cumulative Resistance (MCR) model simulates minimum-cost paths for connecting heritage nodes by constructing resistance surfaces based on environmental variables such as elevation, slope, land use, and accessibility [33,34]. Its advantage lies in producing optimal linear paths under deterministic assumptions. However, MCR tends to oversimplify spatial relationships by focusing on single-route efficiency and ignoring the redundancy and variability of cultural flows. The Cultural Communication Spatial Potential Model (CCSPM) emphasizes the perceptual strength and communicative capacity of heritage nodes, integrating both natural context and symbolic cultural significance to construct paths of cultural influence [35]. While CCSPM offers a richer cultural interpretive framework, it primarily remains a static model and lacks capacity to simulate multi-directional flows or dynamic interactions among nodes. In contrast, the Current Effective Conductance (CEC) theory, derived from circuit theory, introduces a probabilistic and network-oriented approach to modeling landscape connectivity [36,37]. It treats cultural flow as a random walk process, capturing multiple potential paths, flux intensity, and spatial redundancy, which makes CEC particularly suitable for identifying key corridors, bottlenecks, and diffusion zones in complex cultural landscapes. Compared with MCR and CCSPM, CEC provides greater sensitivity to network structure, better simulates real-world uncertainty, and allows for multi-scalar analysis. Therefore, its application in this study aims to advance from deterministic route modeling to a more comprehensive understanding of cultural connectivity in fragmented heritage spaces [38,39,40].

Although current research has made a great deal of progress with regard to a range of cultural resource types, spatial scales, and analysis methods, there is a significant lack of studies related to the historical architectural heritage corridors of Suzhou from the perspective of regional integration, especially those involving systematic construction exploration with architectural heritage as the core while incorporating regional cultural context and water town settlement pattern. As an important representative of Jiangnan culture, it has extremely high cultural connectivity potential and it urgently needs to be expanded in a more systematic and innovative way based on existing research.

2.3. Study on Cultural Relics-Themed Trails

The concept of “trails” as a spatial framework that connects landscape resources, cultural heritage, and public experience originated in the United States. As early as 1921, regional planner Benton MacKaye proposed the trail concept as a linear passage that emphasizes mobility while allowing for scenic appreciation and cultural interpretation [41]. The U.S. National Trails System later institutionalized this concept, defining a “trail” as a pathway that links dispersed natural and cultural resources, equipped with supportive facilities to accommodate recreational activities such as walking, cycling, and driving. Within this institutional framework, trails are regarded as multifunctional corridors for heritage preservation and public leisure.

As the concept spread globally, the concept of a trail has undergone various interpretations and local adaptations. In Italy, cultural trails such as the Via Francigena follow a historical–religious axis, connecting pilgrimage sites from Canterbury to Rome. These trails are characterized by their linear structure, uniform signage, and institutional coordination involving national and regional heritage bodies, and they place emphasis on spiritual continuity, architectural integrity, and historical authenticity. By contrast, UNESCO’s Silk Road heritage corridors span multiple countries and emphasize intercultural dialogue, trade exchange, and transnational cooperation. These corridors are structured around thematic clusters—such as desert oases, Buddhist grottoes, or caravanserais—and are less linear, focusing more on shared heritage narratives and geopolitical frameworks [42,43].

In China, terms such as trail, path, and cultural trail are often used interchangeably depending on disciplinary perspectives. However, cultural relics-themed trails are distinguished by their cultural specificity and interpretive functions. These trails serve as multi-dimensional systems that integrate cultural cognition, ecological awareness, and spatial experience, effectively bridging heritage resources and public understanding. They promote active engagement, stimulate creative cultural production, and contribute to the reinterpretation and revitalization of historical narratives [44].

One of the earliest thematic themed heritage trail practices in China can be traced back to 2006, coinciding with the World Heritage nomination for the Grand Canal. This initiative proposed the design of walkable, perceptible, and interpretable linear heritage paths along the canal, thereby facilitating public interaction with heritage in everyday life. In 2020, China ICOMOS issued the Guidelines for the Construction of Long March Signage and Interpretation System, which advocates for the creation of historical trails that connect significant cultural and natural sites along the Long March trail, thereby enhancing the spatial narrative of collective memory and national heritage [45,46].

In May 2023, the National Cultural Heritage Administration of China, in collaboration with the Ministry of Culture and Tourism and the National Development and Reform Commission, issued a notice promoting the development of cultural relics-themed trails across China. This notice provides an official definition for the connotation, value, and construction objectives of themed trails. According to the notice, a thematic cultural heritage trail refers to a linear heritage system constructed around a specific cultural theme that physically connects dispersed immovable cultural relics [47]. These trails fulfill multiple functions—heritage revitalization, cultural tourism integration, and historical value dissemination—and are categorized into national, regional, and county-level scales. The policy sets forth the goal of piloting 3–5 national-level heritage trails during the 14th Five-Year Plan period, while encouraging local governments to carry out construction based on their own resource conditions [48,49].

Suzhou’s cultural relics-themed trails offer a practical response to the early-stage development of heritage trails in China. Unlike Europe’s pilgrimage trails or UNESCO’s regional corridors, Suzhou’s model focuses on fragmented, diverse heritage sites within a compact urban–rural setting. This study explores how architectural-themed trails enhance spatial connectivity, unify cultural narratives, and promote adaptive reuse under urbanization. By integrating heritage conservation with urban planning and tourism, this research addresses issues such as narrative fragmentation and low public engagement. The proposed framework serves as a planning tool for Suzhou and provides reference value for other historic cities facing similar challenges, contributing to broader discussions on adaptive heritage governance and cultural sustainability.

3. Materials and Methods

3.1. Study Area

Located in southeastern Jiangsu Province, Suzhou is a prefecture city in East China. It borders Shanghai to the east, Zhejiang Province to the south, Taihu Lake to the west, and the Yangtze River to the north. The city is located in the Yangtze River Delta and Taihu Plain regions, with the Beijing–Hangzhou Grand Canal passing through it. Covering an area of 8657.32 km², Suzhou is composed of five districts and administers four county-level municipalities (Figure 1). The city is dominated by flat plains, with a few scattered low mountains and rolling hills, creating a generally gentle landscape profile.

As of December 2024, there are 532 registered immovable historical architectural heritage sites in Suzhou, including 47 national-level key cultural heritage conservation units, 69 provincial-level units, and 416 county and district-level units (

Table 1. The status quo of heritage in Suzhou.

a	b	c	d
e	f	g	h
i	j	k	l

(a) Zhonglou, Soochow University; (b) Jingzheng Building, Soochow University; (c) a modern residence in Miaotang Alley; (d) Tongde Li; (e) Xiyuan Temple; (f) Huang Family Ancestral Hall in Dongshan Village; (g) Tianxiang Cottage; (h) Huang Family Ancestral Hall in Dongshan Village; (i) Lion Grove Garden; (j) Lion Grove Garden; (k) Ouyuan Garden; (l) Ouyuan Garden.

). In addition, Suzhou has preserved numerous historically significant yet current inactive ancient towns and villages. However, making these historical architectural heritage “live” and revitalizing the inactive villages has always been a key issue for heritage conservationists in Suzhou [50].

3.2. Data Source

3.2.1. Cultural Heritage Research Data

The information on Suzhou’s architectural heritage was derived from the “Catalogue of Cultural Heritage Conservation Units at All Levels in Suzhou,” published by the Suzhou Municipal Bureau of Culture, Radio, Television, and Tourism (https://wglj.suzhou.gov.cn/szwhgdhlyj/whbf/201906/d7e226cf3cb543a49044ca851d06c12d.shtml, accessed on 15 May 2025). This includes national-level key cultural heritage conservation units, Jiangsu provincial-level cultural heritage conservation units, and Suzhou municipal-level cultural heritage conservation units. A total of 532 POIs (Points of Interest) were identified, and the X, Y coordinates were obtained using the Baidu Maps coordinate picker (

Table 2. Number and type of historical architecture in Suzhou.

Type	Number
Towers	31
Gardens	28
Former residences of celebrities	180
Bridges	141
Temple	44
Guild hall, school, Yizhuang	47
Significant historical sites and notable structures in modern times	61

). The data were converted to the WGS_1984 grid coordinate system and imported into ArcGIS software version 10.6 to obtain spatial point data.

3.2.2. Basic Data

(1) The Digital Elevation Model (DEM) data and 2018 land use classification dataset, featuring a 30 m spatial resolution, were obtained from the Chinese Academy of Sciences (CAS) Geospatial Data Cloud Platform (https://www.gscloud.cn/). (2) Land use remote sensing data with a spatial resolution of 30 m × 30 m was sourced from the Wuhan University CLCD Land Cover Classification dataset (https://doi.org/10.5281/zenodo.4417809). Based on previous studies and the current topography and geomorphology of Suzhou, the land was categorized into 6 types: grassland, forest, watershed, arable land, unused land, and construction land. (3) OSM vector data for Suzhou’s national highways, roads, provincial routes, and municipal streets were retrieved from the OSM official site (https://openmaptiles.org/languages/zh/#0.47/0/0, accessed on 15 May 2025.).

3.3. Research Framework

The research framework aims to establish integrated land–water heritage corridors in Suzhou and develop scientific cultural relics-themed routes. The research comprises 3 steps: preliminary research preparation, heritage corridor construction, and cultural relics-themed route combing. First, select the research area, collect basic geographic data (including historical building locations, land use, transportation network, digital elevation model (DEM) and other information), and perform spatiotemporal distribution analysis. Secondly, determine the weight of resistance factors by generating resistance surfaces and identifying nodes using AHP, identify potential corridors using CEC model, and verify connectivity through network analysis and Linkage Mapper tools. Classify the corridors to construct a complete heritage corridor network. Finally, based on the heritage corridor network, 6 cultural relics themed routes are proposed, and management recommendations are put forward (Figure 2).

3.4. Research Methods

3.4.1. Kernel Density Estimation (KDE)

Kernel density estimation is an effective tool for spatial analysis, which can provide a direct insight into the clustering and precise distribution of heritage resources within a defined area. This approach can measure and visualize the kernel density of cultural heritage in a particular region, uncovering the spatial clustering characteristics of heritage resources within the designated area [51,52].

Based on kernel density estimation, this research identifies the clusters of heritage resources in Suzhou and highlights the distribution pattern of historical architecture across the city, which provides source data for the clusters of historical architecture, lays the foundation for the development of heritage corridors in Suzhou, and provides key information for the design and planning of heritage space routes.

The common calculation formula is

$$fn\left(x\right)={\displaystyle \frac{1}{\left(nh\right)}}{\displaystyle \sum _{i=1}^{n}k\left(\frac{x-x_i}{h}\right)}$$

(1)

where $fn\left(x\right)$ is the kernel density estimate; $h$ is the nuclear density radius and the search radius; $n$ is the number of point elements; $k\left({\displaystyle \frac{x-x_i}{h}}\right)$ is the kernel function; and $\left(x-x_i\right)$ is the distance from the estimated point $x$ to the sampling point $x_i$.

3.4.2. Average Nearest Neighbor Index

The average nearest neighbor (ANN) distance is a spatial analysis technique that is used to quantify the proximity relationships among point features within a designated area. ArcGIS software can be used to calculate the distance between each point feature and its nearest neighboring point feature, which can further determine the average nearest distance for all points. This method effectively reveals the spatial distribution pattern and clustering characteristics of point features.

An average distance smaller than the expected average distance (ANN < 1) indicates spatial clustering [53].

In this study, the geographic coordinates (POIs) of Suzhou’s historical building heritage resources serve as point features. The average nearest neighbor index has proved effective in evaluating spatial distribution patterns of point features. This analytical method enables precise identification of the clustering characteristics in the spatial distribution of Suzhou’s historical building heritage resources, thereby providing data support for further heritage preservation and planning [54].

The typical calculation formula is as follows:

$$\overline{r}={\displaystyle \frac{1}{n}}{\displaystyle {\sum }_{i=1}^n{r}_i}$$

(2)

$$\overline{{\mathrm{r}}_i}={\displaystyle \frac{1}{2\sqrt{\frac{n}{A}}}}={\displaystyle \frac{1}{2\sqrt{D}}}$$

(3)

$$R=\overline{r}\sqrt{r_i}$$

(4)

where $\overline{r}$ is the average distance of the actual heritage point; ${\overline{r}}_i$ is the average distance of heritage sites when they are geographically distributed; $n$ is the number of sites; $A$ is the total area of the study area; and $D$ is the point density.

3.4.3. Analytic Hierarchy Process (AHP)

The Analytic Hierarchy Process, developed by American operations researcher Thomas L. Saaty in the 1970s, is a popular research approach that integrates qualitative analysis with quantitative methods. The main purpose of AHP is to help decision-makers address complex, multi-criteria decision-making problems by providing a systematic and structured approach. Through the quantification of the importance of various factors, AHP helps in making rational decisions. The common calculation formulas and steps are as follows [55,56]:

(1) Pairwise Comparison Matrix Construction

Suppose there are $n$ factors to be compared, and then construct a $n\times n$ judgment matrix of $A=\left\{a_{ij}\right\}$, where $a_{ij}$ represents the degree of importance of factor $i$ relative to factor $j$.

• For $a_{ij}$, it represents the judgment of the relative importance between factor $i$ and factor $j$. Typically, a scale from 1 to 9 is used (where 1 means that the two are equally important, while 9 means that one party is far more important than the other party).
• The pairwise comparison matrix is symmetric, meaning that $a_{ij}={\displaystyle \frac{1}{a_{ij}}}$, and $a_{ij}=1$.

(2) Feature vector calculation

The eigenvector of the judgment matrix is calculated by the eigenvalue method (such as the maximum feature root method). Feature vector $\omega =\left[{\omega }_1,{\omega }_2,\dots ,{\omega }_3\right]$ represents the weight of each factor. The general steps for solving the eigenvectors are as follows:

• Calculate the maximum eigenvalue of the pairwise comparison matrix ${\lambda }_{\max }$ and the corresponding eigenvector $\omega$.
• Normalize the eigenvectors to calculate the weight of each factor:

$${\omega }_i={\displaystyle \frac{v_i}{{\displaystyle \sum _{i=1}^n{v}_i}}}$$

(5)

where $v_i$ is the element in the feature vector.

(3) Consistency Test

The consistency test is essential to ensure the logical validity and numerical accuracy of the judgment matrix. To assess the reliability of the judgment matrix, the consistency ratio (CR) is calculated as follows:

$$CI={\displaystyle \frac{{\lambda }_{\max }-n}{n-1}}$$

(6)

$$CR={\displaystyle \frac{CI}{RI}}$$

(7)

where $n$ is the order of the matrix and $RI$ is the stochastic consistency index, which can be checked from the standard table. If $CR\le 0.1$, the judgment matrix shows consistency, confirming it falls within acceptable limits. The composite score for each alternative is derived by combining the weights and evaluation scores of each factor. For each scheme, the final composite score $s_i$ is calculated using the following formula:

$$s_i={\displaystyle \sum _{j=1}^n{\omega }_i\cdot x_{ij}}$$

(8)

where ${\omega }_i$ is the weight of the $j^{th}$ factor and $x_{ij}$ is the score of the $i^{th}$ scheme on the $j^{th}$ factor.

3.4.4. Coverage and Evidential Clustering-Based Model (CEC-Model)

The core idea behind the CEC-Model is to simulate current flow in an electric circuit while accounting for the resistance of each element, thereby identifying the optimal current pathways [57,58]. The construction of a CEC-based heritage corridor requires the calculation of current density $J_i$, which reflects the probability of heritage activities to take place. Regions with high current density indicate higher potential for such activities.

The calculation is determined by the following formula:

$$J_i={\displaystyle \frac{V_i}{R_i}}$$

(9)

where $J_i$ is the current density of area $i$; that is, the potential of heritage activities. $V_i$ is the current density of area $i$, which is usually the weighted sum of the influencing factors. $R_i$ is the resistance value of area $i$; that is, the resistance surface data generated by ArcGIS.

The potential value $V_i$ is usually related to factors such as the resource density, historical and cultural value of the area, and can usually be calculated by weighting. The calculation formula is

$$V_i={\displaystyle \sum w_k\cdot f_{ik}}$$

(10)

where $w_k$ is the weight of each influencing factor, and $f_{ik}$ is the score of region $i$ under factor $k$.

Resistance value (resistance surface) $R_i$ is directly generated by ArcGIS, which represents the resistance of each area and is usually related to the physical characteristics of the area. This study incorporates four key physical characteristics among other factors: elevation, slope, aspect, and the road network buffer.

Finally, the corridor suitability $S_j$ can be evaluated by the collective current density, which is calculated as follows:

$$S_j={\displaystyle \sum J_i}$$

(11)

3.4.5. Network Analysis Method

The network analysis conceptualizes the heritage corridor network as a large network made up of nodes and links connecting the corridors. Its principle is based on the “patch-matrix-corridor” concept from landscape ecology, along with three structural indices $\alpha$, $\beta$, $\gamma$ for network evaluation [59]. The calculation formula is as follows:

$$\alpha ={\displaystyle \frac{1-v+1}{2v-5}}$$

(12)

$$\beta ={\displaystyle \frac{1}{v}}$$

(13)

$$\gamma ={\displaystyle \frac{L}{V_{\max }}}={\displaystyle \frac{L}{3\left(v-2\right)}}$$

(14)

where $L$ is the number of corridors; $v$ is the number of nodes; and $L_{\max }$ is the maximum possible number of connections. As for the three indices, $\alpha$ varies between 0 and 1, with values approaching 1 indicating a higher network closure degree; $\beta$ varies between 0 and 3, where increased values correspond to enhanced network complexity and structural stability; and $\gamma$ varies between 0 and 1, with higher corridor connectivity reflected by values closer to 1.

4. Results

4.1. Spatial Distribution Characteristics

This study employs the average nearest neighbor tool in GIS 10.6 to analyze the spatial patterns of the existing 532 historical architecture and cultural heritage conservation units in Suzhou, facilitating the creation of detailed point element layers for enhanced spatial understanding. The results show that the actual nearest neighbor distance of historical architecture in Suzhou is 770.7763 km, while the expected nearest neighbor distance is 2257.0211 km. The average nearest neighbor index is R = 0.34 < 1, with a significance level of p < 0.01 and a Z-score of −29.001. The Z-value test indicates that the historical architectural heritage of Suzhou exhibits significant clustering characteristics in its geographical spatial distribution (Figure 3).

At the spatial scale of Suzhou, historical architectural heritage sources are represented as point features. Based on the spatial distribution data of registered historical architecture, ArcGIS 10.6 is used to conduct the kernel density analysis to identify areas with a high concentration of architectural heritage. The kernel density surface result reflects the intensity of heritage clustering across the region.

To extract representative heritage source nodes for corridor modeling, the study defines high-density zones as areas where kernel density values exceed the mean plus one standard deviation, following established spatial statistical thresholds. Within these zones, local peak values are identified to represent structural concentration centers, yielding a total of 15 source nodes, which are classified by density hierarchy into 1 node of Grade 1, located in the Suzhou ancient city core, with the highest kernel value and centrality; 1 node of Grade 2, corresponding to a sub-peak in the Changshu area; and 13 nodes of Grade 3, representing localized cultural agglomerations with clear morphological identities (e.g., ancient towns, cultural districts, or village clusters). These source points function as origin nodes for the heritage corridor network and reflect the multi-core spatial hierarchy of Suzhou’s heritage landscape (Figure 4).

The results reveal a distinct spatial pattern characterized by “one primary core, one secondary core, and multiple distributed clusters”. The primary core, situated in the ancient city center of Suzhou, accounts for approximately 45% of all registered historical architecture. This area has retained the iconic “dual checkerboard layout” documented in the Song Dynasty’s Pingjiang Map, featuring parallel water and land routes along with a “three vertical, three horizontal, one circular” river network system. The water-based urban fabric, combined with dense historical architecture and classical gardens, creates a distinctive spatial expression of Jiangnan water–town heritage.

The secondary core is located in Changshu. Although its density value is lower than that of the ancient city of Suzhou, it remains significantly above the regional average. The heritage resources here are historically rich, with over 3000 years of urban continuity since the State of Wu. Notably, the area integrates both traditional cultural heritage and distinctive red heritage resources (Red tourism: In the Chinese context, red tourism refers to heritage tourism centered around revolutionary sites, memorials, and historical narratives related to the Chinese Communist Party’s leadership during the New Democratic Revolution period (1921–1949).), exemplified by the Shajiabang revolutionary site.

Beyond these two core areas, several independent heritage clusters have been identified as third-level source nodes based on their local density peaks and spatial significance:

(1) Traditional villages of Dongxi Mountain in western Suzhou, preserving Jiangnan vernacular architecture and the form of the ancient village. (2) Ancient towns in Wujiang District, represented by Tongli, featuring complete water systems and intact urban-river morphology. (3) Ancient Towns in Wuzhong District, such as Lili and Mudu, notable for their historical urban fabric and water–street patterns. (4) Qiandeng Ancient Town in Kunshan, where Ming–Qing architecture remains well preserved, maintaining the integrity of traditional settlement structure.

Overall, the spatial structure revealed by the kernel density surface shows that Suzhou’s heritage landscape is a hierarchical and polycentric system, integrating core nodes, cultural corridors, and peripheral villages. This provides a foundational spatial logic for constructing the subsequent heritage corridor network model.

4.2. Construction of Comprehensive Resistance Cost Surface

Before constructing the Suzhou historical architectural heritage corridor, it is necessary to establish a resistance surface to quantify the spatial resistance that affects the connectivity of heritage points. In order to accurately determine the accessibility and feasibility of the connections in different regions, the study area is divided into grid units, and the initial resistance value is set based on the geographical environment characteristics and human factors. The construction of the resistance surface aims to describe the “spatial cost” that cultural resources need to overcome in the flow of space, and intuitively reflect the spatial friction of cultural exchanges between different grid units, including key factors such as time consumption and path feasibility.

The existing 532 historic architectural heritage sites in Suzhou constitute the fundamental heritage sources for corridor modeling. The resistance factors are generated separately and the resistance surface parameters are set scientifically. This study aims to generate two types of heritage corridors: land-based and waterfront-based, each requiring independent cost surface generation. Based on numerous similar studies, to form a comprehensive cost surface, the land-based heritage corridor highlights four resistance factors in natural environment and transportation infrastructure [60]. From the perspective of the natural environment, the selected factors are elevation, slope, and land use type. For the transportation network, first, a buffer zone analysis of the road network is conducted. Suzhou road network is constructed by integrating highways, national roads, provincial roads, and county roads using the ArcGIS buffer tools. There are five buffer zones established at distances of 10 m, 10–100 m, 100–300 m, 300–500 m, and greater than 500 m, where the spatial resistance decreases with the increase in distances. Areas with higher elevation and steeper slopes have higher resistance values. The resistance values for land use types are assigned according to the intensity of human activities, where regions with greater accessibility or development (such as construction sites) tend to have lower resistance values.

For the waterfront heritage corridor, the cost surface is determined based on two aspects: natural environment and water surface buffer zone. The resistance values for water surface buffer zones are divided into the following segments: 100 m (within which historic architectural heritage can be easily viewed), 200 m and 250 m (representing a 5 min walking distance), and 500 m (representing a 10–15 min walking distance). Distances greater than 500 m correspond to a walking time of over 15 min, where the resistance is the highest for the sightseeing route.

The weights of resistance factors for the heritage corridor network are determined through consultation with 18 experts, who were selected for their diverse disciplinary backgrounds, including architectural heritage conservation, urban–rural planning, ecology, landscape architecture, and tourism studies. The relatively large number of experts ensures comprehensive coverage of both spatial–environmental and cultural–functional perspectives, which are critical for modeling corridor resistance in a complex, multi-dimensional cultural landscape like Suzhou. During the multi-round AHP consultation process, experts assessed the relative influence of four key resistance factors—elevation, slope, land use, and road network density—on the connectivity and permeability of heritage flows. Discussions focused on the ecological sensitivity of waterfront areas, the integrity and accessibility of heritage clusters, and the impact of infrastructural fragmentation. Through iterative scoring and group feedback, the experts reached consensus on the relative weights of each factor, reflecting both expert judgment and local contextual adaptation.

The final weights derived from this process (

Table 3. Categories, classification, and weights of factors for Suzhou land heritage corridors.

Type	Resistance Factor	Weight	Resistance Segmentation
			Resistance Value
Natural environment	Elevation	0.1064	≤5	5–30 m	30–80 m	80–180 m	>180 m
			5	25	60	80	100
	Slope	0.4746	≤3°	3–7°	7–16°	16–30°	>30°
			5	15	50	70	100
	Land use	0.3087	Construction land	Arable land	Grassland	Unused land	Woodland	Water
			5	25	50	70	80	100
Traffic network	Road network	0.1103	≤100 m	100–400 m	400–700 m	700–1000 m	>1000 m
			20	40	70	90	100

) are used to construct the comprehensive resistance surfaces for both land-based and waterfront corridors (Figure 5 and Figure 6), providing a scientifically grounded input for the subsequent corridor modeling.

Using this approach, the weighted sum function in ArcGIS was employed to overlay and assign weights to the resistance values of the four factors, thereby generating comprehensive resistance distribution maps for Suzhou’s land and waterfront regions. The cost–distance analysis was then carried out to calculate the lowest cumulative resistance value, generating the comprehensive cost surface (Figure 7 and Figure 8,

Table 4. Categories, classification, and weights of factors for Suzhou waterfront heritage corridors.

Type	Resistance Factor	Weight	Resistance Segmentation
			Resistance Value
Natural environment	Elevation	0.1204	≤5	5–30 m	30–80 m	80–180 m	>180 m
			5	25	60	80	100
	Slope	0.2192	≤3°	3–7°	7–16°	16–30°	>30°
			5	15	50	70	100
	Land use	0.3915	Arable land	Construction land	Water	Grassland	Unused land	Wood land
			5	25	50	70	80	100
Waterfront buffer area	Waterfront buffer area	0.2689	The waterfront area with a radius of 100 m	The waterfront area with a radius of 250 m	The waterfront area with a radius of 500 m	The waterfront area with a radius of greater than 500 m	The surface of the water
			20	40	70	90	100

).

4.3. Construction of Heritage Corridors

The development of heritage corridors in Suzhou employs established methods of ecological corridor construction, enhancing the region’s cultural landscape. However, variations in resistance values among neighborhoods and villages result in varied accessibility to heritage sites and cultural activities. This disparity not only affects community engagement but also influences construction costs, highlighting the need for tailored approaches to planning and implementation to ensure equitable access to Suzhou’s rich heritage. This study focuses on enhancing visitor activities in the ancient city of Suzhou while maintaining cost-effective heritage preservation. Circuit theory and the Linkage Mapper are employed to create a sustainable model that balances modern usage with the conservation of historical significance [61] and identifies the minimum cost paths for the matter and energy flows among the historic architectural heritage source points within the ancient city of Suzhou. These paths are used as the foundational design for the heritage corridors.

4.3.1. Potential Heritage Corridors and Classification

Suzhou’s land-based heritage corridors are primarily designed around the existing road system, using spatial analysis and optimized pathfinding techniques to create the most efficient routes. During the construction process, high-density areas identified through kernel density analysis are used as heritage source points. The integration of resistance surface with cost–distance analysis helps to determine the most efficient path for the heritage corridor. In this study, circuit theory is used to process the 15 source points one after the other as the starting points for the current and as essential elements in constructing the heritage corridor. By combining all the resistance surface calculations, 27 possible heritage corridors are pinpointed.

Through the classification and grading of heritage corridors, this study further refines the spatial hierarchy and functional characteristics of the corridors, thereby establishing theoretical support for regional tourism planning, route design, and the overall conservation and utilization of heritage. The study uses the Linkage Priority tool to calculate the CSP value (Corridor Priority Value), which reflects the corridor’s serial connectivity, similar to the relationship between voltage and current in a circuit: a higher CSP value indicates stronger corridor connectivity, smoother current flow, and higher network efficiency; conversely, a lower CSP value indicates weaker connectivity and lower efficiency. This indicator provides a quantitative basis for the evaluation of the role and significance of corridors.

The computational analysis of the 27 potential corridors divide them into three levels: 13 corridors of Grade 1, 10 corridors of Grade 2, and 4 corridors of Grade 3 (Figure 9). From a spatial distribution perspective, the corridor levels show a distinct radial gradient from the high-density core of the ancient city of Suzhou to the outer regions. Grade 1 corridors concentrated in the ancient city of Suzhou radiate outwards to sub-core areas (including ancient towns such as Changshu, Wuzhong, and Wujiang), forming the core area of a high-level corridor network and highlighting its importance as the cradle of Wu culture. Grade 2 corridors are mainly distributed around the outskirts of Suzhou’s urban area, as well as in regions such as Wujiang and Kunshan, providing secondary connectivity for the heritage network. Corridors of Grade 3 are located on the periphery of the network, with a more scattered distribution and construction resistance significantly higher than that of the Grade 1 and 2 corridors. By connecting these heritage nodes and clusters, Suzhou can form a clear, hierarchical heritage corridor network, providing an important foundation for the overall conservation, integration, and exchange of regional cultural heritage.

The construction of waterfront heritage corridors is based on the generation of waterfront buffer zones with previously defined indicators. During the construction process, high-value areas identified through kernel density analysis are used as heritage source points. The circuit theory is used to derive the optimal path based on the integration of comprehensive resistance surface and cost–distance analysis. The study suggests 27 potential waterfront heritage corridors by using 15 source points as current starting points in turn and overlaying all the calculation results.

The 27 corridors are classified into 11 corridors of Grade 1, 11 of Grade 2, and 5 of Grade 3 (Figure 10). Spatially, corridor levels decrease outward from the ancient city of Suzhou, with higher levels closer to water, highlighting the importance of waterfront heritage. Corridors of Grade 1 center around the ancient city and extend to Taihu’s East/West Mountains and Wujiang villages, forming a “high-level corridor cluster” that acts as a key hub. Grade 2 and 3 corridors lie in peripheral areas like Kunshan and Taicang, where higher construction resistance suggests weaker connectivity and conservation, indicating a need for further improvement in these zones.

The construction of waterfront heritage corridors is highly innovative. In previous studies, most research focused solely on the construction of resistance surfaces for land-based heritage corridors, with corridor results based on existing vehicular transportation networks, primarily modern roads, while neglecting the influence of regional characteristic factors. In the construction of historic architectural heritage corridors in Suzhou, the waterfront corridors organically combine natural water systems with heritage conservation. The creation of waterfront buffer zones links modern transportation modes with historical waterway routes, forming a more continuous and holistic heritage conservation network. This method not only reflects Suzhou’s unique regional characteristics as a “Jiangnan water town,” but also highlights the city’s water system as a potential historical route and landscape element. Additionally, this approach provides innovative insights for constructing urban waterfront heritage corridors.

The integrated analysis of the results of land and waterfront heritage corridors shows that regions with the highest current density are concentrated along the following four routes: from Suzhou Ancient City to Jinting Town, from Suzhou Ancient City to Kunshan Ancient Town, from Suzhou Ancient City to Yushan District in Changshu, and from Tongli Ancient Town to Zhouzhuang. These areas play a core role in the overall construction and future conservation of the heritage corridor network. Their efficient network connectivity and agglomeration effects provide important support for the overall conservation and coordinated development of cultural heritage in Suzhou. The innovative way of exploring waterfront heritage corridors establishes a foundation for improving and expanding future heritage conservation strategies, while simultaneously offering fresh perspectives and avenues for the preservation and advancement of regional cultural heritage.

4.3.2. Verification of Corridor Connectivity

This study explores the connectivity of heritage corridors using landscape ecology principles. The effectiveness of these corridors as ecological networks is evaluated by applying indices $\alpha$, $\beta$, and $\gamma$, highlighting their importance in preserving cultural and natural landscapes.

As shown in

Table 5. Land corridor connectivity verification index.

$\alpha$	Edges	Nodes	Actual loop	Maximum possible number of loops	$\alpha$ value
	27	15	13	25	0.520
$\beta$	Edges	Nodes	$\beta$ value
	27	15	1.800
$\gamma$	Edges	Nodes	Maximum possible number of connections		$\gamma$ value
	27	15	39		0.692

, the value of index $\alpha$ for land corridors is 0.520, which falls within the range of 0 to 1, indicating that the corridor connectivity is relatively good, with many available loops. This confirms that the heritage corridor network in Suzhou is tightly connected, with a well-developed system that has achieved a closed-loop configuration. The value of index $\beta$ is 1.8, within the range of 0 to 3, indicating that the heritage corridor network is complex and stable, with a high level of road network connectivity. The value of index $\gamma$ is 0.692, within the range of 0 to 1, suggesting that Suzhou’s overall heritage corridor network has a significant number of connecting lines, forming a dense and widely covered heritage network.

As shown in

Table 6. Waterfront corridor connectivity index.

$\alpha$	Edges	Nodes	Actual loop	Maximum possible number of loops	$\alpha$ value
	27	15	13	25	0.520
$\beta$	Edges	Nodes	$\beta$ value
	27	15	1.800
$\gamma$	Edges	Nodes	Maximum possible number of connections		$\gamma$ value
	27	15	39		0.692

, the value of index $\alpha$ for waterfront corridors is 0.520, which falls within the range of 0 to 1, suggesting that the corridor connectivity is quite efficient, with a variety of available loops. It confirms that the Suzhou waterfront historical architectural heritage corridor network has a high closure degree and a well-developed corridor network, reaching a closed-loop state. The value of index $\beta$ is 1.8, within the range of 0 to 3, indicating that the heritage corridor network is complex and stable, with high road network connectivity. The value of index $\gamma$ is 0.692, within the range of 0 to 1, suggesting that Suzhou waterfront historical architectural heritage corridor network has a significant number of connecting lines, creating a robust and widely interconnected cultural heritage network.

5. Discussion

5.1. Spatial System of Heritage Corridors: “One Main Core, One Secondary Core, and Multiple Districts”

To better protect historical architectural and cultural heritage sites in Suzhou, this study proposes a heritage corridor conservation framework of “One Main Core, One Secondary Core, and Multiple Districts” based on the regional characteristics of Suzhou and the distribution of its cultural heritage (Figure 11).

(1)

One Main Core: “The Heart of Gusu’s Ancient Rhyme”

As the core area of the heritage corridor, the Heart of Ancient Gusu is identified by the kernel density analysis as a high-density architectural heritage agglomeration, showing a unique historical and cultural density. Heritage conservation is vital for preserving cultural identity. Establishing a hierarchical conservation mechanism and a zoning management model ensures that heritage units at national, provincial, and municipal levels are effectively managed. This approach aligns with their historical value, promoting sustainable practices that respect and enhance our shared heritage. The approach also emphasizes low-intervention regeneration methods to preserve the historical features, such as restoring structures in their original form and reusing materials [62]; it advocates for activating traditional functions, continuing the lifestyle of the indigenous people and reviving their historical and cultural heritage. Furthermore, the approach also involves the following steps: activate traditional functions, continue the lifestyle of the aborigines, and revive handicrafts, food culture, and study spaces, so as to realize the organic fusion of tradition and modernity; set up buffer zones at the periphery, and strictly control the volumes, heights and styles of newly added buildings, so as to prevent visual clashes and spatial fragmentation; implant green infrastructures, such as rainwater gardens, green roofs, and small-scale open spaces, so as to enhance the ecological resilience and livability of the area, and guarantee the sustainable urban evolution of the area [63]. At the same time, green infrastructure such as rain gardens, green roofs and small open spaces will be implanted to enhance the ecological resilience and livability of the area, and to ensure the continued vitality of the area in urban evolution [64].

(2)

One Secondary Core: The Last Rhyme of Yushan Cultural District

The Yushan Cultural District is located in the north of Suzhou, with Yushan as its center, encompassing the cultural assets of Changshu and its surroundings, and is a secondary architectural heritage agglomeration area identified through the kernel density analysis. Although the heritage density is slightly lower than that of the main core area, the area is known for its blend of landscape and deep cultural traditions, and is one of the important cultural highlands in the southern part of the Yangtze River.

Considering the spatial characteristics of its natural–cultural complex, a holistic cultural–ecological conservation path should be adopted through the following strategies: build a linkage spatial system of cultural landscape–ecological nodes–heritage units; encourage non-commercial development paths, promote the continuation of traditional lifestyles and rural cultural tourism; adopt low-intervention restoration methods; and integrate the heritage in the area. Additional measures include adopting low-involvement restoration methods, strengthening community participation and revitalizing local culture; clarifying the construction boundaries, regulating the building volume, form and style, and guiding the construction in an orderly manner. The above measures aim to consolidate the status of the area as a secondary node of the heritage corridor, and to form a complementary and sustainable spatial pattern with the main core area [65].

(3)

Multiple Districts: Peripheral Cultural Expansion Zone

The peripheral areas of the heritage corridors, such as Wujiang, Kunshan, and Wuzhong, are identified as multi-group areas extending Suzhou’s historical architecture conservation system. Despite the remote geographical location and the low architectural heritage density, the kernel density analysis shows that these areas are distributed with several representative cultural heritage settlements, including traditional ancient towns, ancestral halls, historical bridges and docks, residential buildings, and modern industrial heritage [66].

Specific and differentiated conservation strategies should be implemented according to different heritage types and local development stages: traditional ancient towns should focus on the conservation of spatial patterns and living traditions, and moderately develop tourism to maintain the continuity of local life; religious and public buildings can be combined with repair and moderate revitalization to continue their cultural or educational functions; residential heritage encourages low-intervention reuse, implanting cultural creativity and community functions; and local documents, archives and oral histories should be collected to establish a regional heritage archive and classification system. The above measures will provide a solid foundation for the orderly, controllable and sustainable heritage conservation of peripheral areas [67].

5.2. Build Cultural Relics-Themed Routes Based on Heritage Type

Based on the identified high-traffic paths of historical architectural heritage in Suzhou City through circuit theory, this article further plans and forms six cultural relics-themed routes covering both water and land spaces and connecting various types of heritage [68] (

Table 7. Cultural relics-themed trails.

Number	Route Name	Theme	Key Heritage Nodes	Intended Cultural Experience
1	Ancient City–Majiabang–East–West Mountain Cultural Pilgrimage Route	Cultural Transformation and Spatial Evolution	Suzhou Ancient City, Majiabang Archaeological Site, East–West Mountain Villages	Explore the continuity from Neolithic civilization to literati mountain villages through immersive spatial and ecological pilgrimage
2	Ancient City–South Suzhou Cultural Pilgrimage Route	Silk Craftsmanship and Garden Aesthetics	Suzhou Ancient City, SilkTowns, Tuisi Garden, Duanben Garden	Engage in silk weaving, garden appreciation and traditional craft practices in aesthetic cultural spaces
3	Yushan–Shajiabang–Ancient Town Cultural Pilgrimage Route	Revolutionary Memory and Water Town Heritage	Yushan Academy, Shajiabang Revolutionary Site, Lili Ancient Town	Combine immersive red tourism with water town customs, AR war simulations, and folk performances
4	Ancient City–Traditional Village Taihu Waterfront Cultural Pilgrimage Route	Waterfront Settlement	Suzhou Ancient City, Taihu Lakeside Villages, Traditional Ancestral Halls	Experience layered waterfront architecture and ecological–cultural co-governance
5	Ancient City–Yushan–Qiandeng Ancient Town Yangcheng Lake Waterfront Cultural Pilgrimage Route	JiangNan Culture and Water Town Life	Yushan Academy, Gu Yanwu’s Residence, Qiandeng Ancient Town	Become immersed in the life of ancient townsfolk and literati spirits via water–land hybrid tours
6	Water Town Culture–East Suzhou Ancient Town Waterfront Cultural Pilgrimage Route	Water Network Civilization and Jiangnan Living Heritage	Zhouzhuang, Tongli, Mudu	Explore Jiangnan heritage via waterborne tours and digital storytelling

).

5.2.1. Land Corridor-Themed Cultural Tour Route

(1) Ancient City–Majiabang–East–West Mountain Cultural Pilgrimage Route

As a key themed cultural pilgrimage route within the Suzhou historical architectural heritage corridor system, the Ancient City—Majiabang—East–West Mountain route has a diachronic spatial narrative centered on cultural transformation and spatial evolution. It integrates three cultural themes—urban civilization, prehistoric memory, and landscape settlement—traversing a spectrum of spatial typologies including historical cores, Neolithic sites, and mountainous villages.

In the urban core, the route shows Jiangnan’s spatial adaptability and life-integrated urbanism through traditional streets, brick-wood dwellings, and compact water–town blocks. Fine-grained craftsmanship, harmonious scale, and architectural continuity form the route’s first thematic layer: market–craft–life/culture.

In Majiabang archaeological zone, the route engages with early Yangtze River Neolithic civilization. Through low-intervention exhibits, research facilities, and ecological trails, it establishes a perceptible and educable landscape for prehistoric heritage interpretation, forming a temporal buffer from urban density to open field narrative.

In the East–West Mountain section, the route reaches its cultural synthesis. The integration of mountain-adapted villages, ancestral halls, literati gardens, and temples with topography reflects Jiangnan architecture’s ecological embeddedness and cultural continuity. Unified materiality—blue bricks, black tiles, and wooden structures—conveys a strong regional identity and aesthetic coherence [69].

From the overall route, this themed tour route constructs a multi-dimensional and multi-level heritage conservation system through the phased transformation of cultural content and the linkage of spatial form types. As a structural carrier for heritage conservation and display, it promotes deep integration of cultural localism and public experience, building a heritage conservation path for the Suzhou area that is theme-oriented, spatial-carrying, and continuously updated (Figure 12).

(2) Ancient City—South Suzhou Cultural Pilgrimage Route

Connecting the ancient city of Suzhou with representative cultural nodes in Wujiang, Wuzhong, Kunshan and other places, this route is identified as a corridor with high cultural circulation potential through circuit theory, reflecting the spatial aggregation characteristics of silk craft traditions and garden aesthetics in the southern Jiangsu region. With crafts—ancient town—landscape as the theme axis, it integrates material heritage and intangible cultural expression, providing a shaping path for building a spatial system of participatory cultural experience and heritage interpretation [70].

In the ancient city area, silk production is deeply embedded in the urban spatial texture, and brick and wood workshops and street scales create a multifunctional composite space for production–residence–display. A complete cultural narrative chain can be formed through museums, weaving spaces and live craft venues. This route can achieve the preservation of the material space of traditional crafts and expand the cultural platform for public experience, recreation and contemporary expression.

In the southern area of Suzhou, the cultural theme extends to the aesthetic and life levels. The historical silk town has a high degree of recognition and reuse potential, and can be shaped into a composite cultural field which integrates craft inheritance, cultural education and local tourism. The heritage gardens, such as Tuisi Garden and Duanben Garden, demonstrate the internalized translation of silk culture aesthetics into garden art and living space, which serve as important nodes for constructing a space where cultural images move from crafts to landscape.

Overall, the route becomes a heritage conservation and spatial narrative mechanism that can be used as a reference, showing a gradual transformation from productive cultural space to aesthetic landscape. It reflects the structural interaction between spatial form and cultural theme, and also explores a sustainable path for the integrated conservation of intangible and material heritage in the southern Jiangsu region (Figure 13).

(3) Yushan—Shajiabang—Ancient Town Cultural Pilgrimage Route

This route connects Yushan Cultural Site, Shajiabang Revolutionary Site, and a typical ancient water town, creating a multi-dimensional pilgrimage route that spans historical culture, modern and contemporary revolutionary culture, and water town settlement culture. The route covers the core remains of Wu culture such as Yushan Academy, Xingfu Temple, and Confucian Temple, which are representatives of Jiangnan scholar culture. At the same time, Shajiabang was an important battlefield during the Anti-Japanese War, and its historical sites and memorial halls provide a unique perspective on the combination of revolutionary culture and Jiangnan ecological environment, forming a fusion of “revolutionary culture–traditional water town culture”. Visitors can participate in war simulation experience and red culture theme exhibitions at the Shajiabang Revolutionary Site, reproduce the battles that occurred during the Anti-Japanese War through AR/VR technology, enhance their understanding of revolutionary history, and experience immersive cultural activities such as Jiangnan water town marriage customs, Wupeng boat tours, and water town food-making in the ancient town market [71].

In addition, red dramas and water town folk performances are organized at specific locations to allow tourists to understand Suzhou’s modern and contemporary history in a situational tour. The route is planned according to cultural zones (historical and cultural zone–red cultural zone–water town cultural zone), and the core route (Yushan–Shajiabang–Lili Ancient Town) + expansion route (Zhenze, Tongli and other water towns) are adopted to enable tourists to freely choose cultural themes and meet the cultural experience needs at different levels. In the future, efforts can be made to further develop the revolutionary culture night tour, enhance the vividness of red culture dissemination and enhance the historical memory of tourists through modern means such as light performances, theme concerts, and war image projections (Figure 14).

5.2.2. Waterfront Corridor Themed Cultural Tour Route

In the heritage corridor system, the waterfront cultural tour route uses waterways as a link to connect the historical architecture, ancient towns, cultural landscapes and natural ecology along the route, creating an immersive cultural experience path, allowing tourists to deeply perceive the core position of “water culture” in Suzhou’s history.

(1) Ancient City–Traditional Village Waterfront Cultural Pilgrimage Route

Identified by CEC model, the route is located in the high historical architectural heritage accessible area of the southern waterfront area of Suzhou, connecting the ancient city garden-building complex and the traditional villages along the Taihu Lake. Its spatial structure is based on the nested water body–settlement–building relationship, forming a waterfront cultural pilgrimage route with historical architecture as the core and water environment as the framework [72].

The route covers a variety of building types: the ancient city has densely interwoven gardens, dwellings, guild halls, and the traditional brick and wood structure conforms to the natural environment, which emphasizes the open facade, constructing a multi-level spatial sequence of outward–semi-enclosed–inward living; the ancestral halls and workshops in the village are distributed along the lake, which also reflects the line–point–boundary waterfront construction logic of Suzhou settlements.

In view of the ecological fragility of waterfront heritage, this paper proposes a strategy of zoning identification–low-intervention restoration–community participation: the ancient city section emphasizes scale control and landscape coherence, while the village section promotes resident participation and adaptive renewal to achieve coordinated governance of ecology and culture. As the fulcrum of heritage inheritance and ecological regulation in the cultural relics trail, historical architecture provides a mechanism paradigm for the sustainable renewal of Taihu waterfront cultural heritage (Figure 15 and Figure 16).

(2) Ancient City–Yushan–Qiandeng Ancient Town Yangcheng Lake Waterfront Cultural Pilgrimage Route

Relying on the cultural ecosystem of the Yangcheng Lake Basin, this route connects the ancient city of Suzhou, Yushan Cultural Scenic Area, and Qiandeng Ancient Town. The route highlights the deep integration of the settlement form of Jiangnan water towns and traditional culture. In terms of space, the route connects ancient towns, academies, ancestral halls and gardens along the lake, continuing the structural logic of Jiangnan cultural space. The route serves as a cultural carrier of the distinctive Wu culture, the philosophical legacy of Gu Yanwu, and the lifestyle of ancient townspeople. The cultural nodes—Xingfu Temple, Yanzi Tomb, Yushan Academy and Gu Yanwu’s former residence—embody the academic pursuits and local identity of Jiangnan literati and build an interactive system between the literati spirit and the daily culture of water towns.

The tour experience can be developed around the three major themes of “celebrity culture–folk customs–ancient town life”, and the public’s cultural participation and cognitive depth can be enhanced through immersive forms such as historical situation reproduction, ancient town night tours, academy lectures, and water townsfolk activities. The route employs an integrated land–water strategy to optimize visitor experience and cultural preservation. By reviving the ancient canal waterway and using traditional transportation tools such as painted boats and black-sailed boats, tourists can experience the spatial level of water town settlements while traveling on the water. At the same time, it selects nodes with the most concentrated population in the high-density area to set up cultural stations, constructing a corridor–node–tourism path classification system to enhance the accessibility of heritage and the continuity of cultural inheritance.

The route ultimately brings together the culture, ecology, and local experiences of the Yangcheng Lake region in a coordinated way, creating a new model for heritage preservation, spatial rejuvenation, and cultural tourism integration in Jiangnan (Figure 17).

(3) Water Town–Ancient Town–East Suzhou Waterfront Cultural Pilgrimage Route

This cultural relics-themed tour route revolves around the typical water town cultural settlements in western Suzhou, connecting representative historical towns such as Zhouzhuang, Tongli, and Mudu. It covers multiple cultural heritage resources such as bridges, traditional dwellings, guild halls and temples, constructing a waterfront cultural tour line with both spatial continuity and cultural depth. Most of the ancient towns in the west rely on the evolution of natural waterways to form a settlement pattern with parallel rivers and streets and interlaced water and land, such as the double bridge layout of Zhouzhuang, the Jiuli Sanhe water system of Tongli, and the garden-style street town form of Mudu, all of which reflect the dominant role of water networks in the organization of settlement space [73].

There are various ancient bridges along the route, such as the Fu’an Bridge in Zhouzhuang and the three bridges in Tongli, which constitute the core nodes of the water transportation system and support the mobility and connectivity between ancient towns. In terms of architecture, the water town area is dominated by white walls and black tiles, green tiles and small roofs, and wooden frames, with a distinct regional style. Historical architecture such as Shen Ting, Tuisi Garden, and Yan Family Garden shows the aesthetic and structural characteristics of Jiangnan dwellings. From a cultural perspective, places like guild halls, ancestral halls, and temples—such as Chengxu Daoyuan, Gusong Garden, and Lingyan Temple—function as spiritual landmarks that both honor the history of local families and embody the openness and cultural blending distinctive to Jiangnan. This route integrates multiple ways of sightseeing that combine water and land. Through traditional means of transportation such as rowing boats, painted boats, and water buses, it guides tourists to shuttle between waterways and immerse themselves in the pattern of a town built on water. With the help of digital interpretation and historical scene restoration technology, life fragments such as lectures, transactions and sacrifices are set up in typical heritage spaces to enhance tourists’ cultural cognition and interactive participation. In essence, this route leverages the water network as the framework, the settlement heritage as connecting points, and cultural experiences as the medium, forming a cultural heritage path for Jiangnan. It seamlessly integrates spatial logic, cultural history, and interactive elements, becoming a vital tool for the conservation and promotion of Suzhou’s western water town culture (Figure 18).

5.3. Management Measures for Heritage Resources and Cultural Relics Themed Tour Routes

Suzhou boasts an extensive collection of historical architecture, including cultural and historical districts, traditional areas under the housing and urban planning authorities, and significant cultural heritage sites and conservation areas managed by the department of cultural relics. It also involves multiple categories such as gardens, religions, industries, and residences. These heritage resources fall under different management systems. In the process of systematically constructing themed cultural relics-based tour routes and heritage corridors, it is urgent to establish a comprehensive management mechanism that involves multiple departments. To achieve the coordinated conservation and rational utilization of culture, ecology, and urban functions, this paper proposes the following three management countermeasures:

(1) Establish a cross-departmental coordination mechanism and promote the construction of an integrated management system.

It is suggested that a “joint conference on the conservation of historical architecture and cultural heritage” be established at the municipal level of Suzhou, to coordinate the responsibilities of multiple departments such as housing and urban–rural development, culture and tourism, cultural relics, natural resources, and garden greening, and to promote the connection issues among cultural relics conservation, urban renewal, and tour route construction. A “Suzhou Guideline for the Coordinated Management of Historical Building Heritage and Theme Tour Routes” can be formulated to clarify the responsibilities and divisions of different departments in the delineation of heritage boundaries, assessment of conservation levels, and implementation of tour route construction, thereby enhancing policy execution and systematization.

(2) Build a unified digital heritage platform to achieve resource integration and dynamic management.

It is suggested that the “Suzhou Digital Information Platform for Historical Architecture and Cultural Relics Tour Routes” be built by integrating the data from historical building surveys under the housing and urban–rural development system, the cultural heritage conservation lists at various levels from the cultural relics system, and the evaluation framework for historical architecture proposed in this study. This platform should have functions such as GIS spatial display, attribute data management, status monitoring, and public services, to achieve cross-regional and cross-departmental resource sharing and real-time monitoring, which can provide data support for the optimization of tour routes, the activation and utilization of heritage, and long-term conservation.

(3) Promote a public participation mechanism to facilitate the collaborative governance of “top-down” and “bottom-up” strategies.

It should integrate the conservation of historical architecture and the construction of cultural relics tour routes into the framework of urban–rural integrated development and community micro-updating, and encourage grassroots residents and social organizations to participate in heritage management. Mechanisms such as “volunteer cultural relics protectors” and “tour route guides” can be established, which can grant communities certain rights to protect and interpret aspects of heritage; it can also guide traditional artisans and folk custom inheritors to participate in the cultural activation of heritage spaces along the routes, and build a cultural inheritance network with communities as units and residents as the main body, promoting the formation of a governance pattern of co-construction and sharing.

Through the establishment and improvement of the above mechanisms, we can achieve effective coordination of historical building resources under different management systems in Suzhou, and also provide institutional guarantees and technical support for the systematic advancement of cultural relics-themed tour routes, ensuring the long-term operation and sustainable development of the “corridor–node–tour route” spatial system.

6. Conclusions

This study combines Circuit Effective Conduction theory (CEC) with the ArcGIS platform to analyze the spatial–temporal distribution characteristics and comprehensive resistance surface of historical architectural heritage in Suzhou. It also proposes suitable heritage corridor construction and hierarchical pathways. The results show that the spatial distribution of Suzhou’s historical architectural heritage follows certain patterns and is deeply influenced by natural environmental and socio-economic factors. Using spatial analysis methods such as kernel density estimation and the average nearest neighbor index, this study identifies heritage-dense areas and determines the connectivity and ranking of different heritage nodes based on their historical, cultural, and ecological values. The following conclusions are drawn:

(1) Spatial Distribution Characteristics of Suzhou’s Historical Architecture

The spatial distribution of historical architectural heritage in Suzhou follows a certain pattern. The results show that historical heritage is mainly concentrated in the ancient city and water town regions, which are closely related to Suzhou’s historical development and geographical environment. Natural factors (such as water systems and terrain) and transportation factors play an important role in the spatial distribution of heritage, indicating that the conservation and utilization of heritage need to fully consider these factors.

(2) Heritage Spatial Network Construction and Path Optimization

In this study, 15 heritage nodes are identified using kernel density estimation, and based on the co-construction characteristics of land and waterfronts, two types of heritage spatial networks are constructed. By applying circuit theory to calculate the electrical resistance rate of heritage nodes, this study identifies 27 potential cultural heritage corridor paths, which are categorized according to their significance. Path optimization is used to enhance the connectivity of heritage resources, providing an efficient channel for cultural dissemination between different heritage nodes.

(3) Proposed Optimization Strategies for Heritage Inheritance

This study proposes three optimization strategies: point, line, and surface, which are applied to the spatial network construction of Suzhou’s historical architecture heritage. Among them, the “Point” strategy focuses on dynamic monitoring and conservation of the buildings in the source area, ensuring accurate assessment and timely restoration of heritage resources. The “Line” strategy involves the construction of six cultural pilgrimage routes, both on land and along waterfronts, which include the following:

Land-based cultural pilgrimage routes: Ancient City–Majiabang–East–West Mountain cultural pilgrimage route, Ancient City–South Suzhou cultural pilgrimage route, Yushan–Shajiabang–Ancient Town cultural pilgrimage route. Waterfront Cultural Pilgrimage Routes: Ancient City–Traditional Villages Taihu Waterfront cultural pilgrimage route, Ancient City–Yushan–Qiantang Ancient Town Circular Yangcheng Lake Waterfront cultural pilgrimage route, Water Town–Ancient Town–East Suzhou Waterfront cultural pilgrimage route.

This study examines the spatial distribution and conservation of Suzhou’s historical architectural heritage and proposes an integrated system based on heritage corridors and thematic cultural trails. The framework addresses key issues such as the disconnect between heritage conservation and cultural routes, spatial fragmentation, and lack of regional coordination. Using GIS analysis and circuit theory, the study identifies high-density cultural nodes and models their connectivity, transforming scattered heritage sites into a networked spatial structure. The incorporation of themed trails supports cultural communication, public participation, and heritage reuse, enhancing the visibility of intangible values while maintaining material integrity.

The linkages between the historical city and surrounding districts overcome administrative and functional boundaries, enabling coordinated use of heritage resources across a broader region. The spatial–cultural dual-layer system responds to current challenges in urban heritage planning and provides a platform for cultural renewal, tourism development, and identity reconstruction. The Suzhou case presents a replicable model for integrating cultural resources and supporting living heritage in historical cities.

However, this study has limitations. Urban development pressures may constrain corridor implementation, and the absence of governance integration limits the analysis of institutional feasibility. The reliance on static spatial data also restricts dynamic interpretation. Future research should incorporate real-time data, explore cross-jurisdictional policy mechanisms, and investigate user behavior to strengthen the system’s adaptability and relevance in evolving urban contexts.