Taiwan is located on the Pacific Ring of Fire, the line of seismic faults that surrounds that ocean and where most of the world's earthquakes occur. It is a particularly vulnerable area due to the tension accumulated by the interactions of two tectonic plates, the Philippine Sea Plate and the Eurasian Plate.
The worst earthquake to occur on the island in recent years occurred on September 21, 1999, with a magnitude of 7.7. It caused 2,400 deaths, nearly 100,000 injuries, and destroyed thousands of buildings.