why is denver called the mile high city
Because its official elevation is exactly one mile () above sea level
Denver
 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 () above sea level. The 105th meridian west of Greenwich, the longitudinal reference for the Mountain Time Zone, passes directly through Denver Union Station.
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Denver [SEP] Introduction
The Denver downtown district is immediately east of the confluence of Cherry Creek with the South Platte River, approximately 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 () 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 an estimated 2018 population of 2,932,415 and was the 19th most populous U.S.