The Aspen Backcountry Marathon is one of Colorado’s most stunning trail races, utilizing the world-class trail network that surrounds the legendary resort town of Aspen. All three distances \u2014 the 50K, marathon, and heavy half-marathon \u2014 run almost exclusively on single-track dirt trails with diverse terrain: challenging climbs through aspen groves, high ridge traverses with panoramic views of the Elk Mountains, and technical descents back into the valley. The 50K distance includes an out-and-back to the McNamara Hut, part of Colorado’s storied 10th Mountain Division Hut System. The start and finish at Rio Grande Park places runners in the heart of Aspen.<\/p>\n
The 2026 race takes place on Saturday, August 1, with the 50K starting at 6:00 AM (civil twilight), the marathon at 7:30 AM, and the heavy half at 8:00 AM. The overall elevation gain for each distance challenges even experienced trail runners. Post-race, Rio Grande Park transforms into a festival with live music all day, food trucks, a silent auction, beer, and youth group activities \u2014 all coinciding with the Rotary Club’s Duck Derby fundraiser on the Roaring Fork River at 1:30 PM.<\/p>\n
Few American mountain towns offer trail access as extraordinary as Aspen, and the Backcountry Marathon lets runners experience the best of it in a single event. The combination of world-class trails, Elk Mountain scenery, the community festival atmosphere at the finish, and Aravaipa Running’s reputation for top-tier race production makes this one of the most desirable trail race entries in Colorado. The heavy half option makes the experience accessible to runners who want the Aspen experience without the marathon commitment.<\/p>\n
Aspen sits at 7,908 feet with trails climbing well above 11,000 feet \u2014 plan to arrive at least 2\u20133 days early from sea level. August in the Rockies means afternoon thunderstorms are nearly guaranteed; the morning start is designed to keep runners on exposed ridges before storms develop, but carry a rain shell. The race sells out, so register promptly when registration opens in winter\/spring via Aravaipa Running.<\/p>\n