Great Chikodan Earthquake

The 1860 Chikodan earthquake (行吊單谋铠; chikodan-hokazo), also known as the Great Chikodan Earthquake, was one of the major diasters of the Shi Period. The earthquake occured on April 13th, sometime between midnight and 4am. Its epicentre was located only 2 miles outside of Ashiyumi and caused catastrophic damage to the city, with a death toll of 1,000-2,500. The earthquake had a magnitude of 7.5 and also triggered flooding from the nearby Tao River.

The damage caused by the quake almost completely destroyed the city of Ashiyumi, and almost every ward had to be rebuilt. A multitude of ancient shrines scattered throughout the region were also lost, and it is estimated that almost 20,000 buildings were reduced to debris. Subsequent fires spread throughout the southern and eastern districts, causing extensive damage to any structures that might have survived the tremour. The earthquake resulted in 63 aftershocks, which spread throughout the prefecture with varying intensity.