Integrating space syntax and bathtub flood modelling to assess accessibility impacts of sea-level rise in Copenhagen's historic core

Coastal cities face escalating risks from sea-level rise (SLR), threatening both mobility and heritage preservation in dense urban cores. This study examines the spatial resilience of Copenhagen's historic centre (Indre By) by integrating space syntax accessibility analysis with bathtub-based inundation modelling. The analysis identifies how projected SLR scenarios (0.5 m by 2050 and 1.4 m by 2100) intersect with transport corridors at multiple scales, revealing zones where connectivity loss may severely disrupt pedestrian accessibility, cultural continuity, and everyday urban life. Results show that while central streets such as Strøget and Nørregade retain robust integration, low-lying waterfront areas-including Christianshavn and Holmen-combine high flood exposure with weak connectivity, creating dual vulnerabilities. To address these risks, the paper proposes adaptation strategies such as elevated walkways, resilient waterfront promenades, and green-blue corridors that maintain mobility while enhancing ecological functions. Beyond Copenhagen, the framework demonstrates how combining spatial accessibility metrics with flood modelling can provide a transferable tool for resilience planning in heritage-rich, climate-vulnerable cities such as Venice, Amsterdam, or Mumbai. By linking morphological analysis to policy-oriented adaptation, the study advances a replicable approach for safeguarding accessibility and cultural vitality under climate change.