The City and County of Denver is the most populous city and the capital of the State of Colorado. Denver is located in the South Platte River Valley on the High Plains just east of the Front Range of the Southern Rocky Mountains. The Denver downtown district is located immediately east of the confluence of Cherry Creek with the South Platte River, approximately 15 miles (24 kilometers) east of the foothills of the Rocky Mountains. Denver has a consolidated city and county government. Residents of Denver are known as Denverites.

The United States Census Bureau estimates that in 2005 the population of the City and County of Denver was 557,917 (26th most populous U.S. city), the population of the Denver-Aurora Metropolitan Statistical Area was 2,359,994 (22nd most populous MSA), the population of the Denver-Aurora-Boulder Combined Statistical Area was 2,869,377 (15th most populous CSA), and the population of the Front Range Urban Corridor was 4,013,055. Denver is the most populous city within a radius of 550 miles (885 kilometers). The city claims to have the 10th largest downtown district in the United States.