The City and County of Denver is the capital and largest city of the U.S. state of Colorado. It is located on the plains just east of the Rocky Mountains and forms the heart of the Denver-Aurora metropolitan area. The central downtown district is on the east side of the South Platte River, near its confluence with Cherry Creek, approximately fifteen miles from the foothills. Denver is the county seat of, and shares the same borders with, Denver County — one of the few consolidated city-counties in the United States. According to 2005 Census estimates,[1] the city has a population of 557,917 and ranks as the 25th-largest in the United States and the sixth-largest state capital. The population of the Denver-Aurora metropolitan area is about 2,330,146 (2005) According to Demographia, it is the 20th largest metropolitan area in the United States by 2000 population