The City and County of Denver () is the consolidated city and county that is the capital and most populous city of the U.S. state of Colorado. The population was 715,522 at the 2020 United States census, a 19.22% increase since the 2010 United States census. Denver is the 19th-most populous city in the United States and the fifth most populous state capital. Denver is the principal city of the Denver–Aurora–Lakewood, CO Metropolitan Statistical Area and the first city of the Front Range Urban Corridor.
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 and the South Platte River, approximately 12 mi (19 km) east of the foothills of the Rocky Mountains. Denver is named after James W. Denver, a governor of the Kansas Territory. It is nicknamed the Mile High City because its official elevation is exactly one mile (5280 feet or 1609.344 meters) 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. The 10-county Denver-Aurora-Lakewood, CO Metropolitan Statistical Area had a population of 2,963,821 at the 2020 United States Census, making it the 19th most populous U.S. metropolitan statistical area. The 12-county Denver-Aurora, CO Combined Statistical Area had a population of 3,623,560 at the 2020 United States Census, making it the 17th most populous U.S. primary statistical area. Denver is the most populous city of the 18-county Front Range Urban Corridor, an oblong urban region stretching across two states with a population of 5,055,344 at the 2020 United States Census. The Denver metropolitan area is the most populous metropolitan area within an 560-mile (900 km) radius and the second most populous city in the Mountain West after Phoenix, Arizona. In 2016, Denver was named the best place to live in the United States by U.S. News & World Report.