Riobamba Earthquake

Date: February 4, 1797 • Location: Guano, Ecuador

The Riobamba earthquake, the most powerful in Ecuador's history, devastated Riobamba and many other cities, causing at least 6,000 casualties.

The 1797 Riobamba earthquake occurred at 12:30 UTC on 4 February. It devastated the city of Riobamba and many other cities in the Interandean valley, causing between 6,000 and 40,000 casualties. It is estimated that seismic intensities in the epicentral area reached at least XI (Extreme) on the Mercalli intensity scale, and that the earthquake had a magnitude of 7.6–8.3, the most powerful historical event known in Ecuador. The earthquake was studied by Prussian geographer Alexander von Humboldt, when he visited the area in 1801–1802.