Calabasas is a city in northwestern Los Angeles County, California. It is located in the hills west of the San Fernando Valley and is in the northwest Santa Monica Mountains between Woodland Hills, Agoura Hills, West Hills, Hidden Hills and Malibu, California. As of the 2010 U.S. census, the city population was 23,058. Formerly an unincorporated area of Los Angeles County, the area was incorporated as a city in 1991.