Lancaster /ˈlæn.kæstər/ is a charter city in northern Los Angeles County, in the Antelope Valley of the western Mojave Desert in Southern California. Lancaster currently ranks as the 30th largest city in California, and the 148th largest city in the United States. Lancaster is part of a twin city complex with its southern neighbor Palmdale and together they are the principal cities within the Antelope Valley region and California's High Desert.
Lancaster is located approximately 70 miles (110 km) north (by highway) of downtown Los Angeles, near the Kern County line. It is separated from the Los Angeles Basin by the San Gabriel Mountains to the south, and from Bakersfield and the San Joaquin Valley by the Tehachapi Mountains to the north.
The population of Lancaster has grown from 37,000 residents at the time of incorporation in 1977, to 157,826 people as of 2012. which makes it the largest city in the California portion of the Mojave Desert. According to the Greater Antelope Valley Economic Alliance report of 2013 the Palmdale / Lancaster, CA Urbanized Area (a US Census Bureau defined term) has a population of 513,547.