Trail Running calendar near Frederick 2025-2026

The American Heroes Run, held in Longmont, Colorado, is a patriotic running event commemorating the events of 9/11. It features a variety of distances including a 100-mile ultra with a 30-hour cutoff, a 24-hour run, marathon, half-marathon, 9.11-mile, and 5K races. The course is a flat, fast 1.05-mi..

The Cirque Series at Arapahoe Basin, Colorado, is a challenging mountain trail race held on September 6, 2025. Covering approximately 9.4 miles with 2,411 feet of vertical gain, the course starts at 10,780 feet at Mountain Goat Plaza and ascends through scenic trails including the A-Basin summer roa..

The HRCA Wildcat Mountain Trail Races take place in Littleton, Colorado, starting at the Douglas County East/West trailhead near Rocky Heights Middle School. The event features 10K and 10-mile trail races along the scenic HRCA Backcountry Wilderness Area Wildcat Mountain trail system, offering 100%..

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,..

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

The Ned Ned Half Marathon is a long-standing trail running event held in Nederland, Colorado, celebrating 43 years of tradition. Set in the picturesque mountain town of Nederland at 8,236 feet elevation, the race offers a challenging 13.3-mile course with 1,408 feet of elevation gain, featuring dirt..

The Snow Mountain Ranch Trail Running Festival, held at the YMCA of the Rockies in Granby, Colorado, offers a scenic and challenging trail running experience with race distances of 50K, 33K, Half Marathon, 10K, and 5K. Set amid rolling hills, golden aspen groves, and mountain vistas, the courses fea..

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 Frederick Pack Burro Race is an annual 10K event held in Frederick, Colorado, celebrating the town's Miners Day heritage. The race follows a scenic course starting downtown at Fifth and Oak Streets, heading north along a trail through a tunnel to the Frederick Recreation Area, looping around Mil..

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 three race distances: a 50-mile ultra with 8,500 feet of elevation gain, a 50K with 4,200 feet gain, and a half marathon f..

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 atop the Palmer Divide at 7,240 feet elevation. Surrounded by mountains, the race offers a community-driven atmosphere focused on pushing mental and phy..

The Above the Clouds Ultra is an annual trail running event held in Woodland Park, Colorado, featuring 50K and 10K race distances. Set against the stunning backdrop of Pikes Peak, known as "America’s Mountain," the course offers runners vibrant Colorado fall colors and fast, flowing singletrack trai..

The Castle Rock Trail Festival, held in Castle Rock, Colorado, offers a variety of trail running events on the scenic ridgeline trails of Philip S. Miller Park and Ridgeline Open Space. Distances include a 5K, 10K, half marathon, and an ultra-distance 50K, catering to runners of all levels.Families..

The Bear Chase Race Endurance Festival is a trail running event held at Bear Creek Lake Park in Lakewood, Colorado. It offers multiple distances including 100K, 50 Mile, 50K, Half Marathon, 10K (Baby Bear), and 5K, catering especially to first-time ultramarathoners and trail runners. The course feat..

Rocky's Backyard Ultra is a unique ultra trail race held at the YMCA of the Rockies in Estes Park, Colorado, known as the highest organized Backyard Ultra in the world. Runners complete 4.167-mile laps on a challenging singletrack course featuring about 500 feet of elevation gain and loss per lap, w..

The Suffer Better Fall Trail Run is an annual mountain endurance event held at Staunton State Park, Colorado. The 9th edition, scheduled for October 11, 2025, features challenging courses including 50K and 25K distances, a unique 25K Fishslappers division involving fish catching, and a new 5K race...

The Indian Creek Trail Runs, part of the Human Potential Running Series, is an annual fall trail running event held at Indian Creek Campground in Sedalia, Colorado. Celebrating its 12th year in 2025, the race offers multiple distances: 5-Mile, 15-Mile, 55k, and 50-Mile, with time limits of 12 to 14..

The Great Trailhead Foot Race 10 Miler takes place at Bear Creek Lake Park in Lakewood, Colorado, offering runners a scenic trail experience with single-track dirt paths against the backdrop of Denver's skyline. Participants can choose between a 5-mile or a challenging 10-mile double-lap course. Reg..

The Blue Sky Trail Marathon & Half Marathon, held in Fort Collins, Colorado, offers a scenic and challenging trail running experience through Horsetooth Mountain Park and Devil’s Backbone Open Space. The marathon covers 26.7 miles with 3,500 feet of elevation gain, while the half marathon spans 13.4..