Event details subject to change. Please confirm all information via event website.
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 in New Hampshire. Much of the information for this event is kept secret with an exception for those who are accepted for entry. This is […]
Duck Waddle 5K
Our Vision: Experiencing physical activity with a group encourages motivation, emotional wellbeing, accountability, fun and friendships. By providing athletic events we hope to inspire youth, families and individuals to enjoy building a community. We advocate for safe and connected multi-modal transportation that encourages mobility for all users. Our Purpose: The Estes Park Running Club organizes […]
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 fun-filled day full of fast runners, speed walkers, parents pushing strollers, smiley children, exciting finishes, an epic Diaper Dash, live music and more. Join us […]
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 take and dollar you raise will make a lasting difference for the animals in our care.
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 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'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 goal to shoot for whatever your speed. Just show up an hour before the start and we’ll get you ready for your race. It’s an […]
Emerge 5K
The Emerge 5K is our biggest annual fundraiser, and the funds we raise ensure that we can continue to fulfill our organizational mission of breaking the social and financial barriers to mental health care for youth. Each year, Rise Against Suicide funds thousands of therapy sessions for youth under the age of 19 who are […]
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.
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 globe to support the Best Buddies programs in schools, workplaces, and communities. You’ll be making the world more welcoming to people with IDD — one […]
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