Kern County is a county located in the southern Central Valley of the U.S. state of California. Established in 1866, it extends east beyond the southern slope of the eastern Sierra Nevada range into the Mojave Desert, and includes parts of the Indian Wells Valley, and the Antelope Valley, and has an area nearly the size of New Jersey.

From the Sierras the county extends across the floor of the San Joaquin Valley to the eastern edge of the Temblor Range, part of the Coastal Ranges. To the south the county extends over the ridge of the Tehachapi Mountains. According to the 2000 census, its population was 661,645. The county seat is Bakersfield (since 1874) with the original county seat being the former mining town of Havilah in the mountains between Bakersfield and Tehachapi.