Urban form typologies in Seoul since 1960: A framework for block-level classification and their changing prevalence over time

This study proposes a framework for classifying urban form typologies at the block level and examining changes in their prevalence in Seoul since 1960. The study identifies major typologies aligned with urban planning trends and analyzes their morphological characteristics. Key questions addressed include: how many distinct urban form types can be identified in Seoul; what unique features define each type; and how changes in the prevalence of these types over time reflect broader urban development trends. The analytical procedure consisted of three steps. First, block units were defined based on infrastructure boundaries such as arterial roads. Second, eight indicators were established to capture the morphological features of blocks, parcels, streets, and buildings—the fundamental components of urban structure. Third, Gaussian Mixture Model (GMM) clustering was applied to classify blocks with similar numerical indicators into five distinct types. The result effectively captures how many morphological features aligned with Seoul’s urban planning objectives by era. Compared with previous typologies, the study integrates multiple scales of urban form and examines changes in typology prevalence across different periods, providing a basis for interpreting the historical process of urbanization.