The Calaveras Fault is a major branch of the San Andreas Fault

San Andreas Fault

The San Andreas Fault is a continental strike-slip fault that runs a length of roughly through California in the United States. The fault's motion is right-lateral strike-slip...

 located in northern California

California

California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

 in the San Francisco Bay Area

San Francisco Bay Area

The San Francisco Bay Area, commonly known as the Bay Area, is a populated region that surrounds the San Francisco and San Pablo estuaries in Northern California. The region encompasses metropolitan areas of San Francisco, Oakland, and San Jose, along with smaller urban and rural areas...

. To the east of the Hayward-Rodgers Creek fault, the Calaveras fault extends 123 km, splaying from the San Andreas fault near Hollister and terminating at Danville at its northern end. It runs east of the San Andreas, diverging from it in the vicinity of Hollister, California

Hollister, California

Hollister is a city in and the county seat of San Benito County, California, United States. The population was 34,928 at the 2010 census. Hollister is primarily an agricultural town.-History:...

, and is responsible for the formation of the Calaveras Valley

Calaveras Valley

Calaveras Valley is a valley east of Milpitas. It has formed primarily as a result of the actions of the Calaveras Fault. The southern end of the Calaveras Valley is a few miles south of Calaveras Reservoir, while the northern end is at Sunol....

 there.