Lancaster is a charter city in northern Los Angeles County, in the high desert, near the Kern County line. Lancaster currently ranks as the 30th largest city in California, and the 148th largest city in the United States. Lancaster is the principal city within the Antelope Valley. Lancaster is located approximately 70 miles (110 km) north (by road travel) of the city of Los Angeles in Southern California's Antelope Valley. It is separated from the Los Angeles Basin by the San Gabriel Mountain Range to the south and from Bakersfield and the San Joaquin Valley by the Tehachapi Mountain Range to the north.