A Crack in the Edge of the World

In the early morning hours of April 18, 1906, San Francisco and a string of towns to its north-northwest and the south-southeast were overcome by an enormous shaking that was compounded by the violent shocks of an earthquake, registering 8.25 on the Richter scale. The quake resulted from a rupture in a part of the San Andreas fault, which lies underneath the earth's surface along the northern coast of California. Lasting little more than a minute, the earthquake wrecked 490 blocks, toppled a total of 25,000 buildings, broke open gas mains, cut off electric power lines throughout the Bay area, and effectively destroyed the gold rush capital that had stood there for a half century.