How does pedestrian permeability vary in and across cities? A fine-grained assessment for all large cities in Germany

Pedestrian permeability is a key aspect of the accessibility of urban environments. In particular, high permeability increases the walkability of cities, which is advocated by sustainable urban design practices. Previous research on pedestrian permeability has predominantly focused only on single and very specific, characteristic, and homogenous urban morphologies but investigations at a broader scale have not been conducted up to now. In this paper, we apply the concept of Individual Walkable Neighbourhoods (IWN) to measure local urban pedestrian permeability for all large cities in Germany with more than 100,000 inhabitants. Our results reveal great differences in intra- and inter-urban pedestrian permeability, and based on examples, we explore various factors that influence local permeability, such as topography or structural types. Furthermore, the large-scale analysis is used to identify characteristic patterns of high (e.g., urban centers) or low (e.g., neighbourhoods of single-family detached houses) permeability for German cities.