Event details subject to change. Please confirm all information via event website.
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!
Colterris Wine Run 5K
Colterris Winery 3907 N River Rd, Palisade, CO, United StatesLike Running or Walking? Love Wine? This race is for you! Join us for an exciting annual event that features the amazing scenery and landscape of Colterris Winery! With over […]
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, […]
North Fork Trail Race
BPIA Community Hall 18050 S. Buffalo Creek Road, Buffalo Creek, CO, United StatesThe North Fork 50 Mile/50K is 100% trails, mainly single track and some double track, starting and finishing along lovely Buffalo Creek, in the mountains about 50 miles southwest of […]
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