Trail Running calendar near Windsor 2025-2026

Rock Hawk Trail Races take place in Castle Rock, Colorado, featuring distances of 50K, 25K, 10K, and 5K on the scenic and rolling trails of Phillip S. Miller Park and the Ridgeline Trail systems. The course offers a thrilling yet not overly technical experience, suitable for both novice and experien..

The Calarat Challenge Trail Running Festival takes place in Jamestown, Colorado, at the scenic Cal-Wood Education Center and Balarat Outdoor Education Center. Held over Labor Day weekend, the event features multiple trail races including a half marathon, 10K, 5K, Kids 1K, and combination races like..

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, marathon, half-marathon, 9.11-mile run, 5K, and timed runs such as 24-hour and 6-hour options. The race takes place on a..

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 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 challenging yet accessible experience on a mix of dirt singletrack and road terrain. Runners ascend nearl..

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 Jelm Mountain Run, held in Southeast Wyoming near Jelm Mountain, offers two challenging distances: a 10+ mile out-and-back course and a 50k race that covers the 10-mile route three times. The course features rugged jeep roads with over 2,000 feet of elevation gain, starting at 7,600 feet and cli..

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..

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 dirt trails winding through rolling hills, golden aspen grov..

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..

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

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 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 multiple race distances including a challenging 50K, a 25K with a unique Fishslappers division involving fish catching, and a new 5K..

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..

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..

Beware The Bear Trail Races take place at Bear Creek Lake Park in Lakewood, Colorado, offering 5km, 15km, and a combined 5+15km double race, along with a 1km kids' run. The courses feature mostly dirt trails with a mix of single and double tracks, incorporating short steep hills, rollers, and varied..

The Colorado 24 Hour Run, held in Fort Collins, Colorado, offers a unique endurance running experience on a scenic, flat one-mile dirt loop. Participants can challenge themselves in various timed events including 6, 12, and 24-hour runs, as well as relay options for each duration. The course is desi..

The Bingo! Trail Party is an annual trail running event held at May Farms in Byers, Colorado, organized by the Human Potential Running Series. It offers five distance levels ranging from 6 to 62 miles, accommodating beginners to ultra runners. The unique format involves runners completing loops and..