Land use characteristics of subway catchment areas and their influence on subway ridership in Seoul

This study has dual research objectives: 1) to evaluate the land use characteristics of the pedestrian catchment areas (PCA) of subway stations in the Seoul metropolitan area (SMA) in terms of transit-oriented development (TOD) principles and 2) to investigate the influence of each PCA's land use characteristics on station-level ridership. The major findings can be summarized as follows. First, the built environments of subway PCAs in Seoul were found to be compatible with TOD principles in terms of density and diversity. They have declining density gradients of population and employment that extend outward from a station and have a high level of mixed-use land. Second, population and employment densities, land use mix diversity, and intermodal connectivity all have a positive impact on subway ridership, but differ in their spatial ranges. In particular, the influence spans of residential and commercial development patterns (population density and the proportion of commercial land) and mixed land use on ridership were limited to only the core and primary PCAs. Consequently, with respect to TOD in a compact city like Seoul, we recommend that a PCA be defined to encompass a radius of 600m. •To investigate the relationship between built environments and transit ridership in Seoul.•Built environments of subway PCAs were found to be compatible with TOD principles in terms of density and diversity.•Population and employment densities, land use mix, and intermodal connectivity have a positive impact on ridership.•We recommend that a PCA be define to encompass a radius of 600 m.