Seismic vulnerability challenges sustainable urbanism. Antioch, Manosque and Oran, three Mediterranean cities destroyed by earthquakes, demonstrate how preservation of urban patrimony protects populations. The methodological pattern "urban seismic patrimonial strategies" cross investment and patrimonial care to explain natural hazards mitigation as a factor of urban policy. Urban patrimonial managers are unaware to seismic threat, which obliges to explain liabilities. Buildings evolution observation indicates urban phases. According urban policy but without fatality, natural phenomena reshape urban morphology and amplify social vulnerability.