West Palm Beach, is a city located on the Atlantic coast in southeastern Florida and is the most populous city in and county seat of Palm Beach County, the third most populous county in Florida with a 2010 population of 1,320,134. The city is also the oldest incorporated municipality in South Florida. According to the U.S. Census Bureau, in 2010 the city had an estimated population of 99,919. The city is one of the principal cities in the South Florida metropolitan area, which has a population of 5,564,635.