There are no active volcanoes near Denver, Colorado. Nearby extinct volcanoes are located 2 hours from Denver in the Central Colorado volcanic field. These include the Grizzly Peak and Mount Aetna cauldrons and Bonanza and Marshall Creek calderas. The Central Colorado Volcanic Field is located in Park and Teller counties.
The closest dormant volcano to Denver is Dotsero Volcano, located approximately 2 hours from Denver in Eagle County. It is the only volcano in Colorado that has erupted in the past 10,000 years. Dotsero Volcano last erupted around 2200 B.C. Other volcanoes near Denver include La Garita Caldera, which is located roughly 5 hours from Denver in the San Juan mountains.