Trail Running Calendar Colorado 2026-2027

STRS #5 Carter Park Scurry in Breckenridge on August 12 2026 offers short and long course entries across adult youth and non-binary divisions with published entry fees and a course map.

A high-elevation 100 mile mountain ultramarathon near Durango, Colorado on August 14, 2026, covering roughly 104 miles with about 19,000 feet of climbing, staffed aid stations, required safety gear, satellite tracking, and a 38 hour cutoff.

Point to point half marathon from Ouray to Ridgway, an out and back 10K at Frontier Park, and a one mile kids fun run in Ridgway; proceeds benefit the Mt Sneffels Education Foundation.

A mostly dirt and trail race along Boulder Reservoir in Boulder, Colorado, with about 200 feet of elevation gain. Distances range from a 10K to a full marathon, plus a relay option.

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.

Trail races around Standley Lake in Westminster, CO, with five distances on packed dirt trails and lake and mountain views. Organized by Aravaipa Running; registration closes Aug 10.

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, where runners repeat a 4.167-mile loop each hour until one remains. A single-loop Citizens Race offers a one-time course experience along the Yampa River.

A high-altitude 10K in Leadville on August 16, 2026 that follows the first and last 3.1 miles of the LT100 Run course on paved and dirt roads. One aid station is provided and awards will be given in overall, para and age categories.

A hilly trail 5k at Lory State Park on August 18, 2026 with about 700 feet of elevation gain, a 100-runner cap, chip timing, and pizza and beverages provided after the race.

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 Rocky Mountain Milestone Challenge will take place in Granby from Wednesday 19 August 2026 to Sunday 23 August 2026. You can run between 13 and 100 miles.

A 200 mile loop race through the La Garita mountains around South Fork, CO, reaching elevations just under 13,000 feet. Organized by Tempest Adventures, registration closes Aug 1 and the listed entry fee is 1268 USD.

A 100-mile out-and-back ultramarathon in Leadville, Colorado with about 15,492 feet of climb, a summit at Hope Pass and 11 on-course aid stations.

Experience a high altitude trail run through the Rocky Mountains on 100 percent unpaved roads and trails. This dog friendly event in Fraser supports children facing cancer through the Shining Stars Foundation.

A trail race at Staunton State Park offering 26.3 mile and 13.1 mile courses over mostly singletrack with significant elevation gain, well marked trails, capped fields, and fully stocked aid stations.

A technical mountain race above Telluride, Colorado, with five route options across mining roads, singletrack and alpine tundra. Courses climb to elevations above 13,000 ft and focus on the high-elevation trail experience.

A trail running event on August 22, 2026, offering a 13.3-mile half marathon with substantial elevation and a mostly downhill 5.6K. The race uses Arrowhead, Bachelor Gulch, and Beaver Creek trail networks and includes aid stations for the h..

A cross country meet at Spring Canyon Park in Fort Collins on August 22, 2026, featuring seven races including high school 5k, a community 5k on the same course, and middle school 1.5 mile races. Proceeds support Rocky Mountain High School..