At 7:53 AM local time, on 21 October 1868, the destructive waves from a Magnitude 7 earthquake on the southern end of the Hayward Fault, quickly traveled across the San Francisco Bay Area and beyond.

Because of its location in the heart of the Bay Area, then having a total population of about 260,000, and its magnitude, variously estimated as between 6.8 and 7.0, this earthquake was one of the most destructive in California history. Property loss was extensive and 30 people were killed. Five deaths were reported in San Francisco, out of a population of 150,000, where the total property loss was estimated to be $350,000 ($5-100 Million in 2007 dollars). This earthquake was known as the "great San Francisco earthquake" until the Magnitude 7.9 shock on 18 April 1906. The cracking of the ground along the Hayward Fault was traced about 20 miles (32 km) from San Leandro to Warm Springs in Fremont, although modeling of survey data suggest that the fault moved as far north as Berkeley, and from these data the average amount of horizontal movement along the fault is inferred to be about 6 feet (1.9 meters).

USGS » The 1868 Hayward Earthquake