Aspen Backcountry Marathon

Aspen, United States • 2 Aug 2025

The Aspen Backcountry Marathon, held in Aspen, Colorado, offers three trail running distances: a 50K ultra, a marathon, and a heavy half-marathon. The courses run almost exclusively on dirt trails featuring diverse terrain with challenging ascents, descents, and significant elevation gain, peaking above 10,000 feet. The 50K includes an out-and-back to the McNamara Hut, part of the 10th Mountain Hut System.

The race starts and finishes at Rio Grande Park, coinciding with the Rotary Club's Duck Derby festival, which features live music, food trucks, and family activities. Aid stations are limited, and runners are advised to carry GPS tracks. The event emphasizes stunning views of the Elk Mountains and Aspen cityscape. Visit the organization's website for the most recent information.

Race information

50 km
50 Kilometer
26 mi
Marathon
13 mi
Heavy Half Marathon
Visit the organization's website for the most recent information.
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