1556 Shaanxi Earthquake, China

The Shaanxi earthquake of 23 January 1556 killed approximately 830,000 people — the deadliest earthquake in recorded history. Most fatalities occurred because the population of the densely settled loess plateau lived in yaodong (cave dwellings) carved into soft cliff faces that collapsed completely during the quake. The earthquake caused subsidence of more than 20 metres across an area of 840 square kilometres.