Shasta is one of the 58 counties in the state of California. It was created in 1850, making it one of the original counties of the state. As of the 2010 census the population was 177,233, up from 163,256 in 2000. The county seat and largest city is Redding.
The county covers 3,847.44 square miles (9,964.8 km2), of which 3,785.19 square miles (9,803.6 km2) is land. It is bordered by Siskiyou County to the north, Modoc County to the northeast, Lassen County to the east, Plumas County to the southeast, Tehama County to the south and Trinity County to the west.