Trail Running Calendar Colorado 2025-2026

The High Five 100 is an extreme ultra-endurance running challenge held in Lake City, Colorado. Covering approximately 90 to 105 miles with over 40,000 feet of elevation gain, the course requires runners to summit five 14,000-foot peaks and six 13,000-foot peaks within 48 hours. Unlike traditional ra..

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 area. Beyond the run, participants enjoy a fest..

Pyro's Push It Up Trail Run is a scenic mountain trail race held in New Castle, Colorado, within the Flat Tops-White River National Forest. Participants can choose from three distances: a family-friendly 3.5K, a moderate 7.7K, or a challenging 13K "Double Down" course. The trail features beautiful A..

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 Escape 5K Trail Run takes place at YMCA Camp Jackson in Rye, Colorado, offering participants a challenging 5K run or walk through rugged terrain with over 1,000 feet of elevation gain. The course features wild twists and turns, providing stunning views of Rye and an immersive experience in the S..

The Run the Rockies Trail Race in Frisco, Colorado, offers 5k, 10k, and half marathon distances along scenic trails on the Frisco Peninsula. The course features single track and dirt road trails with stunning views of Dillon Reservoir and the Ten Mile Range. Starting and finishing at the Frisco Nord..

The Buena Vista Pack Burro Race will take place in Buena Vista on Sunday 10 August 2025. You can run between 7 and 13 miles.

The Into the Hills Eltuck 10k is a challenging trail race held at Lory State Park in Bellvue, Colorado. Part of a midweek summer trail series, this event features a hilly 10-kilometer course with approximately 1,700 feet of elevation gain, offering runners scenic mountain views. The race is designed..

The San Juan Softie 100 is a challenging 100-mile ultramarathon held in Durango, Colorado, traversing the scenic San Juan Mountains. The course features an average elevation near 10,000 feet and includes over 20,000 feet of vertical gain, making it a demanding mountain race. Participants experience..

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..

The Cheyenne Mountain Run, held at Cheyenne Mountain State Park in Colorado Springs, offers three trail race distances: 5K, 10K, and a challenging 25K to the mountain summit. The 25K course features a 3,450-foot elevation gain, ascending via Talon, North Talon, and Dixon Trails to about 9,450 feet,..

The Into the Hills Eltuck 5K is a midweek trail race held at Lory State Park in Bellvue, Colorado. Part of a summer trail series, this event features a challenging course with a steep, quick climb and descent along the Homestead, Well Gulch, and Kimmons loop, offering about 700 feet of elevation gai..

The NoCo Urban Ultra will take place in Weld County from Friday 22 August 2025 to Saturday 23 August 2025. You can run between 50 and 100 miles.

The Rio Grande 100 is an ultramarathon held in South Fork, Colorado, starting and finishing along the Rio Grande River. The challenging 100-mile course traverses the La Garita Mountains, featuring diverse terrain from arid forests to alpine tundra, with runners crossing elevations above 12,000 feet..

The Telluride Mountain Run, held in Telluride, Colorado, is a demanding mountain race set in the San Juan Mountains. It offers three challenging distances: 40 miles, 24 miles, and 13 miles. The course features old mining roads, singletrack trails, alpine tundra, mountain passes, exposed ridgelines,..

The Continental Divide Trail Run in Steamboat Springs, Colorado, offers trail races of 5 miles, 16 miles, and 50 kilometers. Set against the stunning backdrop of aspen and pine forests with sweeping views of the Yampa Valley, the courses feature significant elevation gains. The 16-mile race includes..

Staunton Rocks! Marathon & Half is a trail running event held at Staunton State Park in Pine, Colorado, featuring marathon (26.3 miles, 4,500 ft elevation gain) and half marathon (13.1 miles, 2,200 ft gain) distances. The course is predominantly singletrack (90%) with some dirt roads, set at high el..

The Westminster Night Trail in Westminster, Colorado, is a vibrant night trail running event held at Standley Lake. Celebrating its 12th year, it offers distances of 50K, 35K, half marathon, 10K, and 5K, all on 100% packed dirt trails featuring a mix of single-track and bike paths. Runners experienc..

The Byers Peak Stampede Half Marathon & 5K Run takes place in Fraser, Colorado, nestled in the Rocky Mountains about 60 miles from Denver. The event features a challenging half marathon and a 5K race, both primarily on dirt roads and trails with stunning mountain views. The half marathon starts at a..

The Arrowhead Half Marathon & 5K is a scenic trail running event held in Arrowhead, Colorado, part of the Vail Trail Running Series. The half marathon covers approximately 13.7 miles with a challenging 2,924 feet of elevation gain, traversing trails across Arrowhead, Bachelor Gulch, and Beaver Creek..