Trail Running calendar near Keystone 2026-2027

High-altitude trail ultras near Cameron Pass in State Forest State Park: 100 km, 60 km or a double across alpine ridgelines, varied backcountry terrain, marked routes and stocked aid stations with limited entry.

Trail races of 20K, 30K, 50K and 50 mile run from Bear Creek Regional Park in Colorado Springs on July 25, 2026, featuring crushed granite trails, sections with views of Pikes Peak, and summit options on the longest courses.

A non repetitive 200 mile loop around Summit County Colorado that reaches high alpine elevations above 9000 feet. The field is limited to 75 runners, with live GPS tracking, aid and sleep stations, and a 110 hour cutoff.

High-elevation trail and ultra races around Fairplay, Colorado, with 50 Mile, 50k and Half Marathon options, technical and remote terrain, aid stations, drop bags, pacer rules, and a 16 hour time limit.

A trail running event in Aspen on August 1, 2026 offering 50K, marathon and heavy half marathon distances on mostly dirt trails, with remote aid stations, high alpine terrain and a finish line festival alongside the Duck Derby.

Run a scenic mountain 50K or 10K from Winter Park Resort into town with flowing singletrack, aspen groves and views of the Continental Divide. Expect changing high altitude conditions, full aid stations and a finisher award.

Experience the Buena Vista Pack Burro Race in Colorado on August 2, 2026 with long and short courses and options to compete with or without a burro. Finishers enjoy a gift, pizza buffet, free photos and small town Triple Crown charm.

A trail race on the Frisco Peninsula offering 5k, 10k and half marathon courses with lakeshore finishes, chip timing, stocked aid stations, post-race food and beer, and marked single track and dirt trails.

Emerald Mountain Epic in Steamboat Springs on August 8 and 9, 2026 is a two day mountain bike and trail running weekend on scenic singletrack dirt trails. Race marathon, half or bike distances with a limited field of 500 per day.

Run along Boulder Reservoir on flat, mostly dirt trail courses with sweeping Rocky Mountain views. Choose from 10K, 3 4 marathon, half, full marathon or relay, with USATF certified courses, a shirt and a finisher medal.

Roxborough Ultras features 50K and 50M all trail ultramarathons in Roxborough State Park with sustained climbing, technical terrain, and big elevation gain. August is hot and dry with limited shade and spaced aid stations, so carry water an..

Trail races at Cheyenne Mountain State Park feature 5K, 10K and a 25K summit course with about 3,450 feet of elevation gain; the 25K is a Pikes Peak Ascent qualifier and the event raises funds for park trail projects.

Run the scenic Leadville Trail 10K on August 16, 2026 in historic Leadville, Colorado, tracing the opening miles of the LT100 course at over 9,700 feet. Enjoy a fast out and back on paved and dirt roads with aid at the turnaround and awards..

A 99.7 mile out and back ultramarathon in Leadville, Colorado, with 11 aid stations, high altitude passes near 12,526 feet, and belt buckle cutoffs at 25 and 30 hours.

Trail races in Fraser, Colorado on August 22, 2026, offering a Half Marathon and a 5K on unpaved roads and trails. Proceeds support the Shining Stars Foundation and dogs are allowed on leash.

Explore the historic and scenic singletrack trails of Colorado's Staunton State Park. Choose between a full marathon or a half marathon on a high-altitude course with generous time cut-offs. The event includes well-stocked aid stations and..

A trail half marathon and a mostly downhill 5.6K through Arrowhead, Bachelor Gulch and Beaver Creek. The half covers 13.3 miles with about 2,844 feet of ascent, aid stations on course, postrace food, t shirts and age group awards.

Trail races on the Miller Park and Ridgeline trails in Castle Rock offering 50K, 25K, 10K and 5K with aid stations, drop bag support, chip timing and live split tracking; proceeds support local open space and trail efforts.

Trail races of 5 mile, 16 mile and 50K on August 29, 2026 in Steamboat Springs. Mountain courses start and finish at Torian Plum Lawn and climb above 10,000 ft with cupless aid stations.

A family-focused trail event at Arapahoe County Fairgrounds on August 29, 2026, featuring a 5K run, a family 5K walk and a kids 1 mile run. The day includes dog demonstrations, a costume contest, auctions, vendors and a pancake breakfast.