San Bernardino is a city in and the county seat of San Bernardino County, California, United States. Located in the Inland Empire region of Southern California, the city had a population of 222,101 in the 2020 census, making it the 18th-most populous city in California. The Riverside–San Bernardino metropolitan area at 4.74 million residents is the 12th-largest metropolitan area in the nation. San Bernardino is the economic, cultural, and political hub of the San Bernardino Valley, sharing that distinction for the wider Inland Empire with its twin city of Riverside.