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

  • 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 […]

  • 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 […]

  • Duck Waddle 5K

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

    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 […]

    $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 […]

  • Furry Scurry

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

    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 […]

  • Walk MS

    Walk MS
    City Park - Denver 1700 N York St, Denver, CO, United States

    Walk 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. […]

  • 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 […]

  • Frank Shorter Track Classic

    Boulder Track Series
    Niwot High School 8989 Niwot Road, Niwot, CO, United States

    The 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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