Trail Running calendar near Frisco 2025-2026

The Grin & Bear It is Crested Butte’s oldest trail challenge, held in Crested Butte, Colorado. The event features a 25 km loop run, a traditional 15 km out-and-back run, and a new 25 km mountain bike race introduced in 2025. The courses start and finish at the Crested Butte Nordic Center, showcasing..

The Leadville Silver Rush 50M is a challenging 50-mile trail run held in Leadville, Colorado, featuring 7,503 feet of elevation gain and reaching a high point of 12,024 feet. The out-and-back course traverses historic mining roads on the east side of Leadville, offering runners stunning views of the..

The High Lonesome 100 is a challenging 100-mile trail ultramarathon held in the Sawatch Range of the Colorado Rocky Mountains, starting and finishing near Mount Princeton. The loop course features 23,500 feet of elevation gain, reaching a high point of 13,100 feet and averaging 10,600 feet in elevat..

The Audi Power of Four Trail Run is a scenic trail running event held in Aspen, Colorado, featuring routes across the mountains of Aspen Snowmass. Scheduled for July 19, 2025, the race offers three distance options: 50K, 25K, and 10K, catering to a range of trail runners. Participants experience div..

The Spring Creek Memorial Trail Run, held in Steamboat Springs, Colorado, is a scenic trail running event featuring two distances: a challenging 9.5-mile loop and a 5K out-and-back course. The race takes place along the beautiful Spring Creek trail, surrounded by wildflowers, Aspen trees, and bubbli..

The Never Summer 100km & 60km is a challenging mountain trail race held in State Forest State Park near Cameron Pass, Colorado. The event features two distances: a 100km (64.4 miles) with 14,500 feet of elevation gain and a 60km (36.6 miles) with 8,100 feet of gain. The course traverses rugged alpin..

The Elevation Run/Walk is an annual event held in Conifer, Colorado, showcasing the scenic Aspen Park neighborhoods and Meyer Ranch Park at an average elevation of 8,200 feet. The 13th edition, scheduled for July 26, 2025, features a 10K race, a USATF-certified 5K, and a 2-mile fun run, with courses..

The Mountain Fair 4-Miler is a scenic running event held in Carbondale, Colorado, starting near Prince Creek Road and finishing at Sopris Park during the Mountain Fair. The 4-mile course is mostly a gentle downhill, beginning about three miles up Prince Creek Road and descending to Highway 133, then..

The Summit 200 is a challenging 200-mile mountain ultramarathon held in Summit County, Colorado. The race features a single 200-mile loop traversing stunning hiking trails, recreation paths, forest roads, and some pavement, with elevations ranging from over 9,000 feet to peaks near 12,800 feet. Runn..

The Emerald Mountain Epic will take place in Steamboat Springs from Saturday 2 August 2025 to Sunday 3 August 2025.

The Boulder Rez Marathon, held at Boulder Reservoir in Boulder, Colorado, offers a scenic and mostly flat course with only 200 feet of elevation gain. Runners enjoy trails and dirt roads alongside the reservoir, with stunning views of the water and the Rocky Mountains. The event features multiple di..

The Aspen Backcountry Marathon, held in Aspen, Colorado, offers three trail running distances: a 50K ultra, a marathon, and a heavy half-marathon. The courses run almost entirely on dirt trails featuring diverse terrain with challenging ascents, descents, and significant elevation gain, reaching ove..

The Sheep Mountain Ultras, part of the Human Potential Running Series, is a challenging trail running event held annually in Fairplay, Colorado. The race offers three distances: a 50-mile ultra, a 50k, and a half marathon, all starting and finishing at the Town of Fairplay Beach. Set at an average e..

The TransRockies Run is a renowned six-day, 120-mile stage race held in Colorado, offering an unforgettable trail running adventure through the Rocky Mountains. This multi-day event challenges participants with rugged terrain and scenic mountain landscapes, fostering a strong community atmosphere am..

The Holy COW Trail Stampede is a trail running event held in Westminster, Colorado, featuring distances including a 5K and a 10-mile race. Participants enjoy a fun, community-focused atmosphere with a western theme, running through scenic trails near the Westminster Promenade Terrace. All runners re..

The Run the Rockies Trail Race is held in Frisco, Colorado, featuring 5k, 10k, and half marathon distances. The courses traverse the scenic Frisco Peninsula trails, offering stunning views of Dillon Reservoir and the Ten Mile Range. Starting and finishing at the Frisco Nordic Center, the race includ..

Dirt Circus - Boulder is a free community running event held in Boulder, Colorado, celebrating local trail running culture. Organized by UltraSignup, the event features a social group run with options of a casual 4.5-mile or 10K route through the local trails. Beyond running, the festival offers foo..

Pyro's Push It Up Trail Run is a scenic trail running event held in New Castle, Colorado, featuring distances of 3.5K, 7.7K, and a challenging 13K course. The race takes participants through beautiful mountain trails, crossing streams and winding through Aspen groves in the Flat Tops area. It offers..

The Buena Vista Pack Burro Race, held in Buena Vista, Colorado, is a unique 14-mile pack burro running event and the third leg of the 2025 PBR Triple Crown. Participants race alongside their burros, donkeys equipped with pack saddles carrying prospector gear, over challenging terrain that reflects t..

The Leadville Trail 100 Mile Run, held annually in Leadville, Colorado, is a legendary ultramarathon known as the "Race Across the Sky." Established in 1983, this grueling 100-mile out-and-back course challenges runners with extreme Rocky Mountain terrain, starting at 10,200 feet and reaching a peak..