Event details subject to change. Please confirm all information via event website.
Greenland Trail Race
Greenland Open Space 1532 E Noe Rd, Larkspur, CO, United StatesThe Greenland Trail Race offers four outstanding distances in southern Douglas County. Run the 4 Miler, the 8 Miler, the 25K, or tackle the 50K ultramarathon, Colorado’s fastest 50K! With Pikes Peak as your backdrop, you’ll cruise over a soft dirt trail on your way to a new personal best. With chip timing, an innovative technical running shirt in men’s and women’s sizing, food and beer at the finish, this race will make you want to come back for more!
PPRR Nielson Challenge
North Monument Valley Park 1794 Culebra Ave., Colorado Springs, CO, United StatesRace Format The first time you run this event, you'll establish a base time for yourself. This base time is used to generate a handicap time. The handicap time is […]
Niwot’s Challenge
Sedalia Post Office 4195 Douglas Ave, Sedalia, CO, United StatesNiwot’s Challenge is a very difficult, grass-roots, ultramarathon in Colorado’s Front Range. It is modeled after the arduous Barkley Marathons in Tennessee, and the historic More and More Difficult 50K […]
Colorado Marathon
Washington Park - Fort Collins 301 Maple St, Fort Collins, CO, United StatesMarathon, Half Marathon, 10k, 5k and 3-Person Marathon Relay. Marathon, Marathon Relay and Half Marathon runners get to run down the scenic, downhill Poudre Canyon to the finish in Old […]
Longmont Half and 5K
Longmont Rec Center 310 Quail Rd., Longmont, CO, United StatesLongmont's only Half Marathon - now offered in the cooler month of MAY! Join the Half Marathon or 5k distance! Walkers and Runners of all abilities welcome!
Colorado Women’s Classic
Westminster Promenade 10600 Westminster Blvd, Westminster, CO, United StatesWe are excited for the 2026 Colorado Women's Classic! While focused on women, all genders are WELCOME at this event!
Ram Party Trail Runs
Buffalo Lodge Bicycle Resort 2 El Paso Blvd, Colorado Springs, CO, United StatesWith plenty of race options for everybody centered around the beautiful Rampart Reservoir in Woodland Park, Colorado, you're sure to have a good time while you take in the epic […]
Endure Trail Runs
Mueller State Park 21045 State Highway 67, Divide, CO, United StatesThe Endure 12-Hour is a one-of-a-kind challenging 12-Hour timed event, designed by YOU… and tiny colorful balls. Each runner will pull colored balls from a bucket, which determines the loop they’ll […]
Colfax 5K
City Park - Denver 1700 N York St, Denver, CO, United StatesCome join over 21,000 runners from all over the world in the Mile High City! 2 Days, 8 Races means a distance for everyone! 26.2 Marathon through the stadium, fire station, […]
Colfax Marathon
City Park - Denver 1700 N York St, Denver, CO, United StatesCome join over 21,000 runners from all over the world in the Mile High City! 2 Days, 8 Races means a distance for everyone! 26.2 Marathon through the stadium, fire station, […]
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