Trail Running calendar near Denver 2025-2026

The Ram Party Trail Runs is a multi-distance trail running event held at Rampart Reservoir near Woodland Park, Colorado, on May 17, 2025. It offers races ranging from 15K to 55 miles, featuring scenic courses with stunning views of Pikes Peak and the Front Range. The courses include point-to-point a..

The Endure Trail Runs, organized by the Human Potential Running Series, takes place at Mueller State Park in Divide, Colorado. This unique event features a variety of races, including a 10k, Half Marathon, and timed challenges of 12 and 24 hours. Participants in the 12-Hour and 24-Hour events will d..

Samson's Revenge is a trail running event held at the YMCA of the Rockies in Estes Park, Colorado, honoring Samson, the famous elk of the Rockies. The race offers three distances: 10K, 27K, and 55K, featuring fast single-track trails with significant elevation gain, including a challenging ascent of..

The Weld Your Mettle Running Festival is a four-day event taking place in Eaton, Colorado, from May 23 to May 26, 2025. It offers a variety of running challenges suitable for all levels, including a 7K run, ruck, and timed events ranging from 3 to 48 hours, either solo or as part of a relay team. Pa..

The Ol' College Try 24 Hour Ultra is Denver's inaugural 24-hour ultra race, organized by Rise Again Running Events in collaboration with Tall Tales Ranch. Scheduled for May 24-25, 2025, at Auraria Campus, this event invites runners of all abilities to challenge themselves in a non-stop race, fosteri..

The 3rd Latino Ultra Nature Adventure (LUNA) is a unique trail running event scheduled for May 31, 2025, in Boulder, Colorado. This culturally relevant and inclusive event features various distances, including 5km, 7 miles, 15 miles, and a marathon. LUNA aims to promote physical and mental health th..

The Leadville Turquoise Lake 20K is a scenic mountain race held in Leadville, Colorado, featuring a 20-kilometer course around Turquoise Lake. The route begins with 6.5 miles of hilly paved road, followed by 5.5 miles of single-track dirt trail, offering runners stunning views of the surrounding mou..

The Luna (Latino Ultra Nature Adventure) is an inclusive, culturally relevant ultra running event held in Boulder, Colorado. Now in its third year, it offers various race distances, including 5km, 7 miles, 15 miles, and a marathon, all taking place on May 31, 2025. The event emphasizes human-nature..

The Reuter-Hess Trail Incline is a challenging 10k trail race held in Parker, Colorado, featuring about 600 feet of elevation gain. The course begins with a lollipop loop that includes a steep incline with widely spaced stairs, making running difficult. After the incline, runners navigate rolling te..

The North Fork 50 Mile/50K is a premier ultramarathon held in Buffalo Creek, Colorado, about 50 miles southwest of Denver. The event features two distances: a 50-mile race with 6,425 feet of elevation gain and a 50K with 3,670 feet of climb. The course is 100% soft surface, primarily singletrack tra..

The Fish Hatchery 5K Trail Run is an exciting running event set in the picturesque surroundings of the Leadville National Fish Hatchery in Colorado. Participants will enjoy a scenic cross-country course that meanders through subalpine forests and alongside the Evergreen Lakes and lower Rock Creek ar..

The Crazy Legs 10k+ Trail Run takes place at Devil’s Backbone Open Space in Loveland, Colorado. The course features a scenic loop through Hidden Valley, Hunter Loop, Laughing Horse Loop, and Wild Loop trails, covering over 10 kilometers with minimal overlap to prevent congestion. Marked by flour arr..

The Vail Ultra Benefiting 50 For The Fallen is a 50-mile ultramarathon held in Vail, Colorado, starting at The Hangout at Golden Peak. This challenging mountain race offers participants a scenic and demanding course through the stunning terrain of Vail. The event supports the 50 For The Fallen organ..

The adidas Terrex Après 5K Trail Run is a spirited evening trail race held on Vail Mountain, starting and finishing at Nature Valley Mountain Plaza in Vail Village. This 5-kilometer course features diverse terrain including forest service dirt roads, rocky paths, grass, loose gravel, and undulating..

The Great Divide Ultra is a premier trail running festival held in Divide, Colorado, featuring distances of 100 miles, 100K, 50K, and 25K. Set in Mueller State Park, the course showcases stunning spring-fed meadows, massive Pikes Peak granite rocks, and sweeping mountain views. The looped course is..

The Garden of the Gods Ten Mile Run® is a premier race held in Colorado Springs, Colorado, featuring a challenging 10-mile course through the stunning 300-foot sandstone rock formations of Garden of the Gods Park, including the iconic Balanced Rock. The race also offers 10K road and trail run option..

The adidas TERREX 10K Spring Runoff is a challenging trail running event held in Vail, Colorado, at nearly 9,000 feet elevation. Participants race on the scenic Vail Mountain trails, navigating a course with constant elevation changes and diverse terrain including dirt roads, rocky paths, grass, loo..

The Summits Trail Runs, part of the Human Potential Running Series, is an exciting trail running event set in the stunning Rocky Mountains at Granby Ranch Resort, Colorado. Scheduled for June 14, 2025, the event features various race distances, including a challenging 43-mile Quad, a 27-mile Triple,..

The Barr Lake Trail Race, held annually in Brighton, Colorado, offers a scenic and fast trail running experience around Barr Lake State Park. Celebrating its sixth year, the event features multiple distances: 50K, 30K, half marathon, 15K, and 5K, all on flat, dirt terrain with minimal elevation gain..

The Estes Park Backyard Ultra is an endurance running event held along the scenic Lake Estes, supporting Childcare and Family Services. Participants run a 4.252-mile course on a paved bike trail, completing a lap every hour until only one runner remains. The race features no predetermined end time,..