Trail Running calendar near Fort Collins 2025-2026

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

The Frederick Pack Burro Race will take place in Frederick on Saturday 20 September 2025. You can run between 10 and 6 miles.

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 Bear Chase is an endurance trail race festival held at Bear Creek Lake Park in Lakewood, Colorado. It offers multiple distances including 100K, 50 Mile, 50K, Half Marathon, 10K, and 5K, catering to both first-time ultramarathoners and experienced trail runners. The course features mostly dirt an..

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 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, held in October 2025 near Fort Collins, Colorado, offers challenging trail races through the scenic eastern hogbacks of Northern Colorado’s Front Range. The marathon covers 26.7 miles with 3,500 feet of elevation gain, while the half marathon spans 13.4 miles with..

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 will take place in Windsor from Saturday 1 November 2025 to Sunday 2 November 2025. You can run between 6 and 24 kilometers.

The Colleen De Reuck XC Classic is a cross country running event held annually at Harlow Platts Community Park in Boulder, Colorado. Honoring renowned distance runner Colleen De Reuck, the race promotes health, fitness, and celebrates local Olympians, with 2025 honoring 2012 Olympic marathoner Yoshi..

The Bingo! Trail Party is an annual trail running event held at May Farms in Byers, Colorado. Designed as a fun, community-focused "Trail Party," it offers five levels of challenge ranging from 6 to 62 miles. Runners complete loops on a mostly flat course featuring single and double track trails and..

The HRCA Backcountry Wilderness Half Marathon will take place in Highlands Ranch on Saturday 8 November 2025. You can run 13 miles.

The Louisville Trail Race, held annually in Louisville, Colorado, features a Half Marathon, 10K, and 5K, attracting runners to the scenic front range trails. The courses primarily consist of dirt trails with some bike paths, offering mostly flat terrain with challenging hills that provide stunning v..

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

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..

Run the Ranch is an annual trail running event held at the scenic Sylvan Dale Guest Ranch in Loveland, Colorado. The race offers a variety of distances including 5K, 10K, and timed trail runs of 4, 6, and 12 hours, with options for solo runners and 4-person relay teams. Participants run on private r..

The Great Western Trail Race, held in Severance, Colorado, offers a variety of running events including a 5K, 10K, half marathon, and a Kids Fun Run. Scheduled for April 18, 2026, this race welcomes participants to enjoy spring racing in a scenic community park setting. The event features chip timin..

The Weld Your Mettle Running Festival, held in Eaton, Colorado, is a multi-day event featuring a variety of running challenges for all levels. Participants can choose from solo or relay races lasting 3, 6, 9, 12, 24, or 36 hours, including a 100-mile ultra with a 36-hour limit. Unique formats like t..

The Crazy Legs Trail Run will take place in Loveland on Sunday 7 June 2026. You can run 10 kilometers.

The Summits Trail Runs, held at Granby Ranch Resort in Colorado’s Rocky Mountains, offer a challenging and scenic trail running experience with distances from 6 miles to ultra distances including a 50k and a 12-hour Elevation Challenge. The courses feature rugged alpine terrain, single-track trails,..