Event details subject to change. Please confirm all information via event website.
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
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!
RMRR Central Park 5M/5K
Stapleton Central Park 8801 Martin Luther King Jr Blvd, Denver, CO, United StatesEveryone – slow, fast, or in-between – can win at RMRR Trophy Series races. With our handicap scoring system, we predict YOUR finish time based on recent running results, giving you a great […]
Frank Shorter Track Classic
Niwot High School 8989 Niwot Road, Niwot, CO, United StatesThe Frank Shorter Track Classic is a track meet honoring one of America's greatest distance athletes. Each year, we will celebrate Frank's career, his devotion to the sport of running and promotion of health and fitness, while also acknowledging a different Boulder Olympian. This year's meet will take place on May 21st at Nevin Platt Middle School in Boulder.
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