Trail Running calendar near Castle Rock 2026-2027

A looped 10k plus trail run at Devils Backbone Open Space in Loveland featuring marked singletrack, an aid station near mile three served twice, old school timing with a finish stick, and an awards gathering at Loveland Aleworks.

Looped trail races at Barr Lake State Park in Brighton Colorado offer 50K, 30K, half marathon, 15K and 5K options on dirt surfaces with lake and Front Range views. Aid station coverage varies by distance.

Races through Garden of the Gods Park include a 10 mile road, 10K road and 10K trail, all finishing at Rock Ledge Ranch. The routes pass towering sandstone formations, include aid stations, and end with on-site post-race food and music.

A four-race running series in Winter Park, Colorado, from June 14 to August 22, 2026. Events range from a family 5K to half marathons and are scored by a points system with Open Men and Open Women categories.

A three day Leadville training camp that walks and runs major sections of the Leadville Trail 100 course, pairs guided day and night runs with recovery and nutrition support, and includes panels, Q&A sessions and a provided running kit.

A trail race at Garden of the Gods on June 20, 2026, offering 100K, 50K, and 35K courses that feature significant climbing, multiple aid stations, and a start/finish at Rock Ledge Ranch in Colorado Springs.

Experience up to three miles of messy fun at the Colorado National Speedway. Navigate obstacles by crawling wading and sliding through the mud with friends and family during this unique event in Dacono.

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 on June 20, 2026 that combines gravel and road bike rallies, several trail runs, live music, camping and on-site pools. Featured formats include a 100K enduro, a 50K rally and a 5 mile run.

A multi-event Colorado series of four half marathons and a 25K across summer 2026, organized by HAL Sports with races run by local nonprofits. Participants may register for three, four, or all five events.

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 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.

Experience a half marathon in the mountains of Nederland Colorado. This event features a significant elevation gain of 4226 feet with the summit always in view.

A 5k trail race at Alderfer Ranch in Evergreen, CO with a course through Alderfer/3 Sisters Park. Shuttle service runs from Wulf Rec Center and on-site vendors, games, and food are available. Internet registration is not yet open.

A professional pack burro race in Cripple Creek during Donkey Derby Days, featuring a 6 mile urban course, chip timing, checkpoint support, animal welfare rules, on-site activities and monetary awards.

A July 4 community 3.1 mile run from Pueblo city park pavilion along the Arkansas River Trail, with swag bags, costume prizes, finisher medals, music and booths; proceeds support the Southern Colorado Runners Club.

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.