Event details subject to change. Please confirm all information via event website.

  • Collegiate Peaks Trial Run

    Buena Vista Community Center 715 E Main St, Buena Vista, CO, United States

    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

    PPRR Nielson Challenge
    North Monument Valley Park 1794 Culebra Ave., Colorado Springs, CO, United States

    Race 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

    Sedalia Post Office 4195 Douglas Ave, Sedalia, CO, United States

    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

    Lake Estes Marina 1770 Big Thompson Drive, Estes Park, CO, United States

    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 […]

    $30 – $40
  • Hope House 5K

    Westminster Promenade 10600 Westminster Blvd, Westminster, CO, United States

    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

    Washington Park - Denver 701 S Franklin St, Denver, CO, United States

    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, […]

  • Longmont Half and 5K

    Longmont Rec Center 310 Quail Rd., Longmont, CO, United States

    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

    RMRR Trophy Series
    Stapleton Central Park 8801 Martin Luther King Jr Blvd, Denver, CO, United States

    Everyone – 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

    Boulder Reservoir 5565 N 51st St, Boulder, CO, United States

    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 […]

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