Trail Running calendar near Keystone 2025-2026

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 Sawatch Ascent 50k is a challenging high-alpine trail race held in Nathrop, Colorado, showcasing the stunning Sawatch Range. Covering 33 miles with 7,000 feet of vertical gain, the course features a mix of 26 miles of singletrack, paved, and gravel roads. Starting and finishing at the base of Mo..

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 Above the Clouds Ultra is an annual trail running event held in Woodland Park, Colorado, known as the "City Above the Clouds." It features two race distances: a 50K ultra and a 10K run. The course showcases stunning Colorado fall colors and offers fast, flowing singletrack trails around Rampart..

The Bear Chase Race is an endurance trail running festival 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 features m..

The Castle Rock Trail Festival, also known as the liveBIG Run, is an exciting trail running event held in Castle Rock, Colorado, featuring courses through the scenic Philip S. Miller Park and Ridgeline Open Space. It offers a variety of distances to suit all levels, including a 5K, 10K, half maratho..

The Pikes Peak Road Runners Fall Series will take place in Colorado Springs from Sunday 5 October 2025 to Sunday 23 November 2025. You can run between 3 and 7 miles.

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 Great Trailhead Foot Race 10 Miler, held at Bear Creek Lake Park in Lakewood, Colorado, offers 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. Registratio..

The Bobcat Trail Race, held in Palmer Park, Colorado Springs, is a celebrated urban trail running event showcasing the park's rugged beauty and panoramic views of the city and Pikes Peak. Organized by Aravaipa Running since 2024, it offers four race distances: 50K, 25K, 10K, and 5K, catering to a ra..

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, it offers four race distances: 5-Mile, 15-Mile, 55k, and 50-Mile, with time limits of 12 to 14 hours dependi..

The Beware The Bear Trail Races, held at Bear Creek Lake Park in Lakewood, CO, offers a variety of race options including a 5km, 15km, and a kids' 1km run. The courses feature mostly dirt trails with a mix of steep hills and rolling terrain, making it suitable for both beginners and experienced trai..

The HRCA Backcountry Wilderness Half Marathon is an annual trail race held in Highlands Ranch, Colorado, featuring a challenging 13.1-mile course that showcases stunning landscapes. Participants navigate through dirt, gravel, and singletrack paths, with opportunities to encounter local wildlife. The..

The Louisville Trail Race, held annually in Louisville, Colorado, features a Half Marathon, 10K, and 5K, attracting runners to the scenic front range trails. Celebrating its 12th year, the event offers mostly dirt trail courses with some bike path sections, showcasing the stunning Flat Irons and fro..

The Colorado Cold Rush Ultra is a winter trail running event held in Colorado Springs, featuring distances of 50K, half marathon, and 10K. The race courses showcase diverse terrains and stunning views, including historic High Drive and the tunnels from the Colorado gold rush era. The 50K starts at B..

The Thumbs Up Vertical Challenge is an 8-hour ascent race held in Estes Park, Colorado, on the Thumb Open Space trail. Participants run a 1 km out-and-back course with a steep 540-foot elevation gain per ascent. Runners collect poker chips at the turnaround point to track their completed ascents, wh..

The Sawmill Trail Runs, part of the Human Potential Running Series, is an annual trail running event held at Staunton State Park in Pine, Colorado. Offering 50k, 16-mile, and 8-mile distances, the race features a scenic and challenging course through diverse terrain ranging from high grassy meadows..

The USCSA Cross Country Ski Racing Festival, held at Snow Mountain Ranch Nordic Center in Granby, Colorado, is a vibrant collegiate and junior skiing event scheduled for January 24-25, 2026. It features classic races of 15 km and 7.5 km for college and independent high school athletes, alongside CHS..

Stories Trail Runs is an annual winter trail running event held at Cheyenne Mountain State Park in Colorado Springs, Colorado, offering stunning views of Cheyenne Mountain and Pike’s Peak. The event features multiple race options including timed 30-hour, 15-hour, and 6-hour ultras, as well as shorte..

The Winter's End Snowshoe Races, held at Granby Ranch Resort in Granby, Colorado, offer a unique winter running experience on mostly groomed single and double-track trails. The event features multiple distances including a marathon, 14-mile, 7-mile, and 5k races, accommodating runners of all skill l..