What major earthquake and fire devastated San Francisco in 1906?

The major earthquake and fire that devastated San Francisco in 1906 was the 1906 San Francisco earthquake.

The earthquake struck on April 18, 1906, along the San Andreas Fault. It had an estimated magnitude of about 7.9 and severely damaged San Francisco, Santa Rosa, San Jose, and other Northern California communities. The shaking collapsed buildings, ruptured water and gas lines, and disrupted transportation and communications.

Fires soon became even more destructive than the initial earthquake. More than 30 fires burned for approximately four days, destroying about 25,000 buildings across 490 city blocks. Because much of the firefighting infrastructure was damaged and some firebreak efforts went wrong, the flames spread through large parts of the city. More than 200,000 people became homeless.

The death toll remains uncertain because many Chinatown fatalities were not recorded at the time. Historical estimates range from roughly 700 to more than 3,000, with San Francisco later recognizing 3,000-plus as its official figure. A common mistake is treating the disaster as only an earthquake: the earthquake began the catastrophe, but the ensuing fires caused most of the physical destruction.