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

  • 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
  • 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!

  • Hayden Cog Run

    Hayden Town Park 229 South 3rd Street, Hayden, CO, United States

    The Hayden Cog Run is one of the longest consecutively run races of the Steamboat Springs Running Series and in the state of Colorado! This is a Routt County Classic […]

  • Quad Rock Trail Race

    Lory State Park 708 Lodgepole Dr, Bellvue, CO, United States

    Welcome to the Quad Rock 50 and 25 mile trail races, an event put on by trail runners for trail runners. Taking place on the trails and hills west of […]

    $125 – $170
  • Valkyrie Women’s Trail Race

    Cheyenne Mountain State Park 410 JL Ranch Heights, Colorado Springs, CO, United States

    Valkyrie Trail Race was created as a women only trail/ultra event,  featuring Colorado Spring’s, Cheyenne Mountain State Park.  The race offers amazing views of the city and a diverse eco-system. We have several […]

  • CMRA Tucker Lake 6.5

    Colorado Tap House - Arvada 14982 West 69th Avenue, Arvada, CO, United States

    The race will start near the Colorado Tap House parking lot and head west along the Ralston Creek Trail toward Tucker Lake. Once reaching Tucker Lake runners will loop around […]

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