Greenland Trail Races

Niwot's Challenge is a demanding ultramarathon held in Colorado's Front Range, inspired by the Barkley Marathons. This grassroots event, limited to 40 participants, emphasizes navigation skills as runners traverse mostly off-trail terrain using only a map and compass. The challenge includes various..

The Mountain Ridge Trail Race, held in Highlands Ranch, Colorado, offers scenic trail running options for all levels, including 5K, 10K, half marathon, and 21-mile courses. Set on the Douglas County East-West Regional Trail, the race features rolling hills, dirt and single-track trails, and manageab..

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..

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..