The City of Cañon City (IPA: /ˈkænjən ˈsɪti/) is a Home Rule Municipality that is the county seat an the most populous city of Fremont County, Colorado, United States. The United States Census Bureau estimates that the city population was 16,000 in 2005. Cañon City is famous for being the site of 9 state and 4 federal prisons. It straddles the Arkansas River, and is a popular tourist destination for Whitewater rafting and rock climbing.