Event details subject to change. Please confirm all information via event website.
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 Town, Fort Collins, where we have live music and a big post-race party featuring beer from Odell Brewing Company. For 2027 Boston Marathon qualifiers, races […]
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 views of Pikes Peak and the front range. 55 Mile | 60K | 50K | 24K | 15K
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 next run. This continues for up to 12-hours in time, and the runner’s result is the number of miles they ran within the allotted time. […]
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, downtown, Sloan’s Lake, Colfax Ave, 7 miles of water 13.1 Half Marathon through Denver Zoo, Denver Fire Station, downtown, Colorado Firefighter Calendar on course Urban 10 […]
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, downtown, Sloan’s Lake, Colfax Ave, 7 miles of water 13.1 Half Marathon through Denver Zoo, Denver Fire Station, downtown, Colorado Firefighter Calendar on course Urban 10 […]
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 Denver. This is a pure ultra, a very special and unique race, deliberately kept small so each runner gets personal attention. There are no non-ultra […]
Harvest Moon Triathlon
Boulder Reservoir 5565 N 51st St, Boulder, CO, United StatesEst. in 2000 this Colorado classic provides the veterans to beginners a challenging, affordable, and competitive race with a local flavor. Whether this is your first event of the season, or a tune-up for a summer long course triathlon, don't miss the Harvest Moon! The Aquabike portion is one of the fastest growing Aquabikes in […]
Boulder Stroke & Stride I
Boulder Reservoir 5565 N 51st St, Boulder, CO, United StatesThe Boulder Stroke & Stride enters its 24th season in 2025, and offers Boulder area athletes a fun 1-lap 750 Meter Swim, or 2-lap 1500 Meter swim in Boulder Reservoir, followed by a 5k run on the reservoir dam on 8 Thursday evenings (plus one Wednesday evening) throughout the summer. Many participants make their open-water […]
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