Trail Running Calendar Colorado 2026-2027

Trail races in Colorado Springs with 100K, 50K and 35K courses that start and finish at Rock Ledge Ranch in Garden of the Gods, featuring significant elevation gain, aid stations, and on course support.

The Muddy Dash - Denver will take place in Dacono on Saturday 20 June 2026.

A trail run at Creekside Park on June 20, 2026 offering 10K and 5.2K courses as part of the Vail Trail Running Series; the race benefits the Vail Valley Charitable Fund and features aid stations, finish-line food, awards, and on-site maps.

Test your strength at this exclusive obstacle course event in Peyton featuring a three lap 3K race and a one mile kids run. Navigate rigs, rope climbs, and heavy carries in a small field of only fifty athletes.

A one day festival in Lyons Colorado combining gravel and road bike events, trail running races, live music, pool areas and camping. Distances include 100K and 50K gravel rides plus a 5 mile run and several relays.

Four Colorado mountain events include four half marathons and a 25K across June to September 2026, totaling 67.9 miles. The series is coordinated by HAL Sports with nonprofit organizers supporting local youth programs.

A community-focused trail festival in Gold Hill, Colorado, with 28K, 12K, 5K and Kids 1K races, a shuttle from Boulder, and proceeds supporting wildfire preparedness for the town.

At 10,600 feet in Alma, Colorado, Race in the Clouds is a June 25 to 28 Dirt Fest featuring mountain biking, trail running, off road duathlon, youth races and meadow camping, with USA Triathlon sanctioning and age group awards.

A rugged, mostly off-trail 50k around Silverton, CO, with about 19,000 ft of ascent and a roughly 19-hour cutoff. Entry is limited and restricted to club members with proven mountain navigation experience.

Trail races at Lory State Park on June 27, 2026 featuring 10 mile, 5 mile and 5K courses with treetop views of Horsetooth Reservoir and aid stations using biodegradable cups and dog water bowls.

A 26.4 mile trail marathon and a 15.46 mile Heavy Half on Leadville mining trails, topping out at Mosquito Pass 13,185 feet. Both races feature multiple aid stations, specified parking and shuttle arrangements, and the marathon serves as an..

Chase the Moon is an overnight fixed time trail event in Highlands Ranch, Colorado with solo 12, 6 and 3 hour races, a 50K and three and five person relays. Runners complete marked loops on dirt trails with aid stations and drop bag support..

A backyard ultra on the paved Lake Estes trail where runners complete 4.252 mile loops each hour until one runner finishes a loop alone. The event records yards for DNFs and offers on-site aid and athlete village space.

SBT TRL in Steamboat Springs offers trail races at Howelsen Hill as part of the SBT GRVL weekend. Participants can choose a 5 km or 10 km distance with registration open from February 10 to June 27, 2026.

Operation HAYSTACK is a half marathon in Nederland, Colorado on June 27, 2026. The course covers 13.1 miles with 4,226 ft of elevation gain and the listed entry price is $105 plus tax.

A three race trail series at Sunlight Mountain Resort near Glenwood Springs, Colorado. It offers 5K, 10K, and a half marathon with specified elevation gains, limited aid station support, and defined registration windows.

A 10 kilometer trail race at Alderfer Ranch in Evergreen Colorado on June 27 2026. The event includes shuttles from Wulf Rec Center, vendor tents, on-site food and water refill stations while the course is supported by course marshals.

A professional pack burro race in Cripple Creek on June 28, 2026, held within the Donkey Derby Days festival. The 6 mile course features chip timing, staffed checkpoints, cash prizes, and family activities at the start and finish.

A 5K run/walk in Winter Park, Colorado following the Fraser River Trail from Gondola Plaza to the Rendezvous Event Center, with an after party featuring refreshments, awards and prize giveaways.

A Fourth of July 5K in downtown Leadville, CO, held above 10,000 feet. Proceeds support local youth athletics and youth entries are free.