Event details subject to change. Please confirm all information via event website.
Greenland Trail Race
The 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!
Collegiate Peaks Trial Run
The Collegiate Peaks Trail Run takes place in Buena Vista, Colorado and offers two race distance options - 25 miles and 50 miles. The race was established in 1991 and […]
Niwot’s Challenge
Niwot’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 […]
Duck Waddle 5K
The DUCK WADDLE 5K race begins at east side of Estes Park Parking Structure. Each runner and walker will follow the scenic Lake Estes Trail counterclockwise to the finish line (west of […]
Hope House 5K
Our 13 annual Hope House 5K & Fun Run will take place on Saturday, May 2, 2026 at the Promenade Terrace Park (South of the Westin Westminster)! It will be a […]
Furry Scurry
The Furry Scurry is an annual, fun-filled festival and two-mile dog walk at Denver’s Washington Park to benefit the animals at the Dumb Friends League. No matter where you scurry, every step you […]
Colorado Marathon
Marathon, 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'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!
Best Buddies Friendship Walk
The Best Buddies Friendship Walk is the leading event in the country supporting inclusion for people with intellectual and developmental disabilities (IDD). Join 50,000 participants at 70+ Walks across the […]
Quad Rock Trail Race
Welcome to the Quad Rock 50 and 25 mile trail races, an event put on by trail runners for trail runners. Taking place on the trails and hills west of […]
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