Trail Running calendar near Boulder 2025-2026

Run rugged single and double track trails at Mueller State Park with distances from 10k to marathon and a playful 12 hour loop where colored balls pick your next lap. One main aid station, scenic views, and on site camping.

The Weld Your Mettle Running Festival, held in Eaton, Colorado, is a multi-day event featuring a variety of running challenges for all levels. Participants can choose from solo or relay races lasting 3, 6, 9, 12, 24, or 36 hours, including..

North Fork 50 : Event details The North Fork 50 Mile/50K is scheduled for Saturday, May 30, 2026, in Buffalo Creek, Colorado. The start and finish are at the Buffalo Creek Clubhouse, 18050 S Buffalo Creek Rd, Buffalo Creek, CO 80470. Distan..

Enjoy alpine single track through meadows and aspen groves at Granby Ranch Resort with distances from 6 Mile to 50k and a unique Elevation Challenge scored by total climb rather than distance. Small field and stocked aid stations make for a..

Great Divide Ultra in Divide, Colorado on June 6-7, 2026 offers looped 25k to 100 mile trail races in Mueller State Park plus the Dark Divide Night Run. Smooth single and double track winds through rolling meadows with stunning Pikes Peak v..

Run the Crazy Legs 10k+ at Devils Backbone Open Space in Loveland, Colorado, a scenic singletrack course with aid stations and lively local support. Limited spots remain and this is the event's final year, so grab your spot now.

Race in the Clouds - Alma Dirt Festival 2026 The Race in the Clouds - Alma Dirt Festival is a multi-sport outdoor event held in Alma, Colorado in 2026. The festival base is Alma Cemetery Meadow, at about 10,600 ft elevation and roughly half..

Timberview Trail Run is held at Lory State Park in Bellvue, Colorado, just outside Fort Collins. The event offers three distances: 5K, 5 Mile, and 10 Mile (the 10M is a double loop of the 5M). Runners traverse scenic forest trails with view..

Run high in the Rockies at the Life Time Leadville Trail Marathon and Heavy Half in Leadville, Colorado on June 27, 2026. Tackle mountain trails to Mosquito Pass above 13,000 feet and chase Leadville Trail 100 qualifying spots.

Event overview The Silverheels Trail Runs take place July 10-11, 2026, with start/finish operations based at the Como Roundhouse in Como, CO. Distances offered include: 100-Mile 100k 50-Mile 60k 19-Mile 10-Mile Runner capacity is limited:..

Take on the Silver Rush 50 in Leadville, Colorado, a scenic trail and dirt road 50 mile mountain challenge with about 7,500 feet of climb and a high point near 12,024 feet. Top finishers can earn a Leadville Trail 100 qualifier coin.

Event overview The Never Summer races take place in July 2026 around Gould, Colorado, mostly inside State Forest State Park between the Never Summer Mountains and the Medicine Bow Mountains. Distances offered: 100 km (65.7 miles) 60 km (39..

The Summit 200 is a rugged 200 mile loop around Summit County Colorado, climbing about 40,000 feet on high alpine trails. Capped at 100 and requiring a prior 100 mile finish, it rewards experienced runners with a scenic high altitude test.

Join the Wild West Relay, a scenic point to point 200 miles across Colorado from Fort Collins to Steamboat Springs. Run solo or with teams from 1 up to 12 people as you tackle mountain passes, open roads and big western views.

Event overview The Sheep Mountain Trail Runs is the 12th annual event held in Fairplay, Colorado, with the Start/Finish at the Town of Fairplay Beach. The race has a runner capacity of 300 and a time limit of 16 hours. The course sits at an..

The Lory Summer Trail Series will take place in Bellvue from Wednesday 5 August 2026 to Wednesday 26 August 2026. You can run between 5 and 12 kilometers.

Run the Rockies Trail Race in Frisco, Colorado offers 5k, 10k, and half marathon distances on the scenic Frisco Peninsula trails, with views of Dillon Reservoir and the Ten Mile Range. The start and finish are at the Frisco Nordic Center. T..

The Byers Peak Stampede Half Marathon will take place in Winter Park on Saturday 22 August 2026. You can run between 5 and 21 kilometers.

The Leadville Trail 100 Mile Run will take place in Leadville on Saturday 22 August 2026. You can run 100 miles.

Front Range Ultra Dayze invites 200 runners to tackle a flat two mile loop along River's Edge in Loveland with multi day timed and classic ultra options. On site camping, communal meals, and a welcoming vibe.