Castle Rock Trail Festival

The Greenland Trail Races, set in southern Douglas County, Colorado, features a variety of running events including a 50K ultramarathon, 25K, 8M, and 4M races. Participants can enjoy scenic trails with Pikes Peak as a backdrop, aiming for personal bests on soft dirt paths. The event includes chip ti..

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, taking place on May 10, 2025, in Highlands Ranch, Colorado, offers a variety of distances for trail running enthusiasts, including a 21-mile, half marathon, 10K, and 5K. Celebrating its 11th year, the race features scenic dirt and single-track trails with manageable el..

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 Reuter-Hess Trail Incline is a unique running event held in Parker, Colorado, featuring a challenging 10k course and a 1-mile kids' race. The race employs a handicap start system, allowing participants of varying ages and genders to compete on an equal footing. The course includes a steep inclin..

The North Fork 50 Mile and 50K ultramarathon takes place in the scenic Colorado mountains near Buffalo Creek. The course features nearly all singletrack trails, with some double track sections, traversing diverse landscapes including burn areas from a 1996 fire, ponderosa pines, and granite rock for..