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!
High Line Canal Run
deKoevend Park 6315 S. University Blvd., Centennial, CO, United StatesThe 45th Annual High Line Canal 5K & 10K race takes place along the beautiful High Line Canal Trail. Registration includes post-race pancake breakfast.
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 provides a significant challenge of not only time but also physical and mental stamina. Beginning and ending near the Arkansas River in Buena Vista, the […]
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 calculated using an algorithm developed by Bob Royse, and it's geared to favor a beginning runner and the slower runners. Click here for an explanation of the […]
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 as […]
Denver Beer Company 50K
Denver Beer Company - Arvada 5768 Olde Wadsworth Blvd, Arvada, CO, United StatesCompete as an individual or a relay team. This unique urban odyssey 50k run connects all 5 Denver Beer Co. Taprooms. Join us for the Denver Beer Co. 50k run on Saturday, May 2, 2026. This unique urban odyssey 50k run connects all 5 Denver Beer Co. Taprooms (Olde Towne Arvada > Platte St. > […]
Furry Scurry
The Furry Scurry is an annual, pet-friendly, fun-filled festival and two-mile dog walk at Denver’s Washington Park to benefit the animals in our care. This year, people can gather in person on Saturday, May 2 OR walk from afar between now and May 11 (although we hope you’ll choose May 2 for your “virtual” stroll)! No matter where you scurry, […]
Walk MS
City Park - Denver 1700 N York St, Denver, CO, United StatesWalk MS includes a powerful new experience where you’ll witness how your support changes the lives of people with MS and gets us closer to our ultimate goal: a cure. Whether you live with MS, love someone who does, or are a part of the wider community, you can proudly display your role in the […]
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