History must not repeat itself-urban geological safety assessment is essential

Urban geohazards have been frequently triggered by extreme natural events in recent decades. In July 2021, the extreme rainfall in Zhengzhou, China killed 292 people, left 47 people missing, and caused thousands of ground collapses. This disaster alarms for the assessment of urban geological safety around the world. Strengthening the assessment of urban geological safety and preventing catastrophes caused by potential extreme natural events are essential in urban construction.