Denver, officially the City and County of Denver, is the capital and most populous municipality of the U.S. state of Colorado. Denver is located in the South Platte River Valley on the western edge of the High Plains just east of the Front Range of the Rocky Mountains. The Denver downtown district is immediately east of the confluence of Cherry Creek with the South Platte River, approximately 12 mi east of the foothills of the Rocky Mountains. Denver is nicknamed the Mile High City because its official elevation is exactly one mile above sea level. The 105th meridian west of Greenwich, the longitudinal reference for the Mountain Time Zone, passes directly through Denver Union Station.
Denver is ranked as a Beta- world city by the Globalization and World Cities Research Network. With an estimated population of 704,621 in 2017, Denver is the 19th-most populous U.S. city, and with a 17.41% increase since the 2010 United States Census, it has been one of the fastest-growing major cities in the United States.