Certain pedestrian facilities, by their nature and the spatial imperatives they impose, exert a powerful role in organizing and promoting the development of associated central places. The need for an expanded public space in the city has found expression in the new public spaces that have emerged in relation to this transport infrastructure within long developed urban environments. In contemporary, advanced urban society, such new spaces need to have polyvalent purposes and to respond to emergent demands. It is proposed that certain characteristics of these pedestrian systems support intensification and multiplication of activities over a particular spatial environment defined by activities. In the three cases—the Underground system of Montreal, Tokyo Station City and the Central Mid-levels Escalator area—common characteristics proposed as important to the achievement of the developmental goals include specific spatial relations, system open-endedness and structural complexity.