Qinglong An, Chiho Ochiai
The integration of historical flood adaptation strategies into contemporary resilience planning remains a critical challenge for heritage cities in flood-prone areas. This study addresses this gap by proposing ‘Planning Heritage’ as a key analytical lens, conceptualizing it as the cumulative outcome of evolving planning paradigms and flood response strategies. Employing a mixed-methods approach that combines historical document coding, GIS mapping, Space Syntax analysis, and fieldwork, the research examines how chronic flood pressures have shaped the urban form of the Ancient City of Linhai, China, over centuries. The findings reveal that Linhai’s flood mitigation capacity relies on a synergistic system of tangible elements (city walls, street networks, and water systems) and intangible wisdom (defence and diversion strategies, alongside community participation). Crucially, the urban morphology has co-evolved with flood risks, resulting in spatial configurations that inherently support evacuation efficiency, drainage, and adaptive land use. However, qualitative evidence suggests that the contemporary functional relevance of this heritage is currently threatened by fragmented management. Consequently, this study concludes that planning heritage constitutes a vital resilience resources and advocates for its active integration into modern flood mitigation planning. This necessitates a paradigm shift from passive preservation to functional revitalization, performance enhancement, and institutional coordination, effectively linking cultural heritage conservation with sustainable flood risk reduction.