Bakersfield is a city in California, United States, and the county seat of Kern County. It covers about 142 square miles (370 km2) 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 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 (by value) in the United States. Industries include natural gas and other energy extraction, aerospace, mining, petroleum refining, manufacturing, distribution, food processing, and corporate/regional headquarters. The city is also the birthplace of the country music genre known as the Bakersfield sound.