Trail Running Calendar Colorado 2026-2027

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.

Leadville Trail 10K on August 16, 2026 is a 6.2-mile out-and-back on paved and dirt roads using the opening and closing sections of the LT100 Run course. The race features one turnaround aid station, branded on-course nutrition, and multipl..

A hilly trail 5k at Lory State Park Eltuck Picnic Area in August 2026, capped at 100 runners and timed by chip. Post-race pizza and beverages are provided and the race is part of an August series of trail events.

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 on August 22, 2026, featuring high alpine terrain and a peak at Hope Pass. The course covers about 99.7 miles with around 15,492 feet of elevation gain and includes 11 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.

Trail races in Arrowhead, Colorado on August 22, 2026 include a 13.3 mile half marathon with 2,844 ft of climbing and a mostly downhill 5.6K. Courses run mostly on single track and finish at Arrowhead Village with awards and post race food.

A half marathon trail race in Evergreen, CO that reaches the summit of Bergen Peak. Organized by the local parks district, the event includes vendor tents, refreshments, a cup-free policy and course marshals.

A fast, flat 12 km trail race on the Valley Trail at Lory State Park, part of a four-race August series. Entrants are capped and timed with chips; vintage race shirts and post-race food and beverages are provided.

Rock Hawk in Castle Rock, Colorado runs on the Miller Park and Ridgeline trails with 50K, 25K, 10K and 5K options. The event features cup-free aid stations, drop bags, chip timing and live split tracking.

Trail races held from the Torian Plum Lawn in Steamboat Springs offering 50k, 16 mile and 5 mile options across high alpine terrain with cupless aid stations, limited crew access, and awards including finisher mugs and age group prizes.

A community trail event at the Arapahoe County Fairgrounds on 08/29/2026 with a 5K run, a family 5K walk that allows leashed dogs, and a kids 1 mile plus demonstrations, vendors, and a pancake breakfast.

Run Like the Wind in Allenspark on August 29, 2026 features a 5K race, a 2K run/walk and a dog jog option. Proceeds benefit The Old Gallery and participating dogs are entered in an amateur dog show.

A high elevation 50 mile mountain race in Ouray, Colorado on August 29, 2026. The course has 23,582 feet of climbing, required pre race volunteer service or a $100 opt out donation, and mandatory tracked location reporting.

A 5k trail run starting at 11,000 feet at Copper Mountain on August 29, 2026, presented by Mammut. The run takes place during the Union Peak Festival, which includes live music and festival activities afterward.