San Bernardino County, officially the County of San Bernardino, is a county located in the southern portion of the U.S. state of California, and is located within the Greater Los Angeles area. As of the 2010 U.S. Census, the population was 2,035,210, making it the fifth-most populous county in California, and the 12th-most populous in the United States. The county seat is San Bernardino.
Riverside County, is one of fifty-eight counties in the U.S. state of California. As of the 2010 census, the population was 2,189,641, making it the 4th-most populous county in California and the 11th-most populous in the United States. The name was derived from the city of Riverside, which is the county seat.