Bakersfield is a city in and the county seat of Kern County, California, United States. It covers about 142 square miles near the southern end of the San Joaquin Valley and the Central Valley region. Bakersfield's population is approximately 365,000, making it the ninth-most populous city in California and the 52nd-most populous city in the nation. The Bakersfield–Delano Metropolitan Statistical Area, which includes all of Kern County, had a 2010 census population of 839,631, making it the 62nd largest metropolitan area in the United States. The more built-up urban area that includes Bakersfield and areas immediately around the city, such as East Bakersfield, Oildale and Rosedale, has a population of approximately 464,000.The city is a significant hub for both agriculture and oil production. Kern County is the most productive oil producing county, and the fourth most productive agricultural county in the United States.