Cerritos, formerly named Dairy Valley because of the preponderance of dairy farms in the area, is a suburban city in Los Angeles County, California, United States, and is one of several cities that constitute the Gateway Cities of southeast Los Angeles County. It was incorporated on April 24, 1956. As of the 2010 census, the population was 49,041. It is part of the Los Angeles?Long Beach?Anaheim, California Metropolitan Statistical Area designated by the Office of Management and Budget.