Trail Running Calendar Colorado 2026-2027

A two day untimed trail event at New Belgium Ranger Station in Snowmass Village offering 3.76k, 5k and a 10k plus an 18.76k Centennial Challenge. Includes a free New Belgium craft brew, finisher medal and event festivities.

Trail races of 5k, 10k and half marathon on Frisco Peninsula trails with lake and mountain views, single-track sections, chip timing, aid stations, and post-race food and beer for participants 21 and older.

Two day mountain bike and trail running event in Steamboat Springs on August 8 and 9 2026. Multiple distances from a 52 mile solo bike to 26.2 and 13.1 mile runs, with proceeds supporting local youth and trail organizations.

Trail races of 16 mile and 8 mile take place at Rampart Reservoir near Woodland Park, Colorado. Pre registration is required and parking is on USFS Roads 950 and 951 with about a quarter mile walk to the start.

A traditional pack burro race at 10,200 ft in Leadville, Colorado on August 9, 2026. Teams of a runner and a burro follow marked mountain routes over historic mining trails with long and shorter course options and strict animal welfare rule..

Experience a focused trail run through the hills of Lory State Park with 1,700 feet of elevation gain. Enjoy a post-race social with pizza and beer in a scenic outdoor setting limited to 100 participants.

A four‑race midweek trail series at Lory State Park in August 2026 offering 5k, 10k and 12k courses with varied elevation. Series and per-race registration, post-race food and drinks, and end-of-series awards for top points scorers.

The Summit Trail Running Series will take place in Frisco on Wednesday 12 August 2026.

A high-mountain 100 mile ultramarathon north of Durango, Colorado, with about 19,000 ft of climbing and a 38 hour cutoff. The 2026 race is sold out; satellite tracking and specific mandatory gear are required.

A multi-distance race at Boulder Reservoir, Colorado, featuring a mostly dirt and trail course with about 200 feet of elevation gain and views of the reservoir and the Rocky Mountains.

Trail ultras from Roxborough State Park to Sharptail Trailhead featuring sustained climbs, technical singletrack, and a long runnable finish, with full aid support and an emphasis on land stewardship.

Experience the trails of Cheyenne Mountain State Park with three race distances ranging from a 5K walk to a 25K mountain challenge. This chip timed fundraiser supports park conservation through scenic and high elevation courses.

A multi-distance trail event at Standley Lake in Westminster, Colorado featuring 50K, 35K, half marathon, 10K and 5K on packed dirt trails with aid stations, drop bag access, parking at Wayne Carle Middle School and lakeside views of the Fr..

Summit Grays and Torreys Peaks in this 8.8 mile Colorado endurance event. Participants must carry a 20lb dry load while tackling 4,101 feet of elevation gain.

A community Backyard Ultra at Loudy Simpson Park in Craig, Colorado, with repeated 4.167 mile loops each hour until one runner remains. A single loop Citizens Race uses the same riverside course for a shorter experience.

The Leadville Trail 10K Run on August 16, 2026 is a 10 km out and back that uses the opening and closing sections of the LT100 Run course at high elevation, with one aid station at the turnaround and age group and overall awards.

Experience a hilly 5k trail race through the scenic Lory State Park. Enjoy a low key atmosphere followed by pizza, beverages, and a vintage race shirt in this midweek summer series event.

A four‑race midweek trail series at Lory State Park in August 2026 offering 5k, 10k and 12k courses with varied elevation. Series and per-race registration, post-race food and drinks, and end-of-series awards for top points scorers.

A 60 hour endurance challenge at Snow Mountain Ranch where runners repeat a 10 mile trail loop to reach milestone distances. Entry includes lodging, meals, training and recovery services.

La Garita 200 is a 200 mile mountain loop that starts and finishes in South Fork on the banks of the Rio Grande. The route rises to just under 13,000 feet and passes through pine forest, alpine tundra and mountain parks.