Trail Running Calendar Colorado 2025-2026

The American Heroes Run, held in Longmont, Colorado, honors the memory of 9/11 with a variety of race distances on a flat, fast 1.05-mile loop course. Events include a 100-mile ultra with a 30-hour cutoff, a 24-hour run, a marathon, half-marathon, 9.11-mile run, 5K, and unique timed runs reflecting..

The Cirque Series - Arapahoe Basin is a challenging mountain running event set for September 6, 2025, in Keystone, Colorado. Participants will tackle a 9.4-mile course with an elevation gain of 2,411 feet, starting at 10,780 feet. The race features three divisions: Sport, Expert, and Pro, catering t..

Devil on the Divide is a challenging trail running event held in Empire, Colorado, featuring 50K and 22K point-to-point courses. Set against the stunning backdrop of Clear Creek County and the Continental Divide, the race offers breathtaking views and high-altitude terrain, with the 50K course reach..

The Black Squirrel Half Marathon is a challenging 13.5-mile trail race held in Lory State Park near Fort Collins, Colorado. Featuring approximately 2,000 feet of elevation gain and loss, the course offers a scenic perimeter tour of the park with stunning views of Horsetooth Reservoir, Fort Collins,..

The HRCA Wildcat Mountain Trail Races, scheduled for September 6, 2025, in Littleton, Colorado, features a variety of events including a 10K, 10M, and a Kid's Race. The race begins at the Douglas County East/West trailhead and takes participants through the scenic HRCA Backcountry Wilderness Area. R..

The Breckenridge Oktoberfest 5K is a festive running event held in historic downtown Breckenridge, Colorado, as part of the annual Oktoberfest celebration. This 5K trail run takes participants through scenic Town of Breckenridge Trails, showcasing beautiful fall foliage and changing aspens. The race..

Run Rabbit Run is a challenging ultra-running event held in Steamboat Springs, Colorado, featuring 50-mile and 100-mile races through the scenic Routt National Forest. The 50-mile course starts at the Steamboat Springs ski area (6,900 ft elevation), ascending to Mount Werner (10,568 ft), crossing th..

The Blisters & Brews Telluride 5k will take place in Telluride on Saturday 13 September 2025. You can run between 5 and 5 kilometers.

Snow Mountain Ranch Trail Running Festival, held in Granby, Colorado, offers a scenic and challenging trail running experience with race distances of 50K, 33K, Half Marathon, 10K, and 5K. Set at the YMCA of the Rockies, the courses feature 100% dirt trails winding through rolling hills, golden aspen..

The Ouray 50 Mile Endurance Run, held in Ouray, Colorado, is a challenging mountain ultramarathon featuring approximately 23,582 feet of elevation gain. Known for its technical and demanding trails, the course is set nearly two miles above sea level amidst stunning mountain scenery. This race is des..

The Ned Ned Half Marathon is a long-standing trail running event held in Nederland, Colorado, a picturesque mountain town at 8,236 feet elevation. Celebrating over 43 years, the race features a challenging 13.3-mile half marathon with 1,408 feet of elevation gain, traversing dirt roads and single-tr..

The Pony Express Trail Run is a scenic trail race held at Rampart Reservoir near Woodland Park, Colorado, at elevations between 9,000 and 9,400 feet. Offering two distance options—8.5 miles and 16 miles—the course features rolling single-track dirt trails with rocky sections and exposed roots, inclu..

The Ouray Mountain Trail Run is a challenging 13-mile race held in the scenic mountains of Ouray, Colorado, starting and finishing at Fellin Park. Participants are treated to stunning views and the unique charm of the town. This event serves as a fundraiser for the Ouray School, supporting education..

The Pikes Peak Marathon, held in Manitou Springs, Colorado, is a challenging mountain marathon known as "America's Ultimate Challenge." The race covers the full marathon distance and requires participants to complete a qualifying run due to the demanding trail to the summit of Pikes Peak. The event..

The Red Feather Trail Jamboree is a three-day trail running event held at Ben Delatour Scout Ranch in Red Feather Lakes, Colorado. Scheduled for September 26-28, 2025, it offers races of 50 miles (8,500 ft gain), 50K (4,200 ft gain), and a half marathon (1,700 ft gain), traversing moose-populated fo..

The WILD Wahatoya Runs, held in La Veta, Colorado, offers a scenic and historic trail running experience in the Cuchara Valley near the Spanish Peaks. Named after the Wahatoya mountains, meaning “Breasts of the Earth,” the event features three distances: a 50K, a challenging half marathon, and an 8-..

The Deep Creek Trail Half Marathon is a scenic 13-mile trail race held near Telluride, Colorado. Starting at the Telluride Airport on Last Dollar Road, runners descend to Deep Creek Corral before entering singletrack trails through aspen-filled woods along Deep Creek. The course offers a mix of terr..

The 24 Hours of Palmer Lake is an endurance running event held in Palmer Lake, Colorado, featuring a 24-hour race on a scenic 0.82-mile loop course. Situated atop the Palmer Divide at an elevation of 7,240 feet, the course offers beautiful mountain surroundings. This community-driven event focuses o..

The Golden Leaf Half Marathon is a scenic running event held annually in late September, starting at Fanny Hill in Snowmass and finishing at Koch Lumber Park in downtown Aspen, Colorado. The course follows the Government Trail, winding through beautiful Aspen groves, offering runners a picturesque a..

The Crested Butte Ultra, held in Crested Butte, Colorado, offers runners a chance to experience some of the nation's best trails through the stunning Gunnison National Forest. The event features multiple distances, including a 50-mile, 55K, and 35K race. Participants traverse single-track trails tha..