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

  • Boulder 5K Taco Run

    Boulder Public Library 1001 Arapahoe Ave, Bouler, CO, United States

    Super charge your Taco Crushing appetite with a run before the Boulder Taco Fest! A non-competitive fun run on some of Boulder’s most beautiful multi-use paths. There’s even an aid station with some Boulder Taco Fest-themed treats. You’ll finish up back at the Boulder Taco Fest, ready to celebrate your run at Boulder’s favorite summer […]

  • Pioneer Prairie Dog Half Marathon

    Prairie Dog Race Series
    Westminster Promenade 10600 Westminster Blvd, Westminster, CO, United States

    Welcome to the Pioneer Prairie Dog Half Marathon event; the one that started the series! With 10k and 5k events too! Everyone is back to school and slipping into a routine. Make this your mental health break as you break away from the chaos of weekly schedules and give yourself a morning to race in […]

  • Log Hill Hustle​ 5K/10K

    Divide Ranch and Club 151 Divide Ranch Cr, Ridgway, CO, United States

    Join us for the Annual Log Hill Hustle 5K & 10K, a scenic fun run/walk hosted by Fortuna Tierra Club in support of local education. Set against the stunning backdrop of the San Juan Mountains and Cimarron ranges, both courses begin and end at the beautiful Divide Ranch and Club, winding along gently rolling, fully […]

  • Wellington Swim-Run Challenge

    Wellington Lake Wellington Lake Rd. Pike National Forest, Bailey, CO, United States

    Swimmers may choose to swim with their shoes, paddles, a wetsuit, pull buoy, floaties, rubber duckies, inflatable flamingoes or any other nonmotorized swim aid in this event. Race Course Per Lap = 0.3 M Swim, 1.6 K Run Total: 3 Laps = 1 Mile Swim, 5K Run

  • Rebel Run 5K

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

    Join Conservation Colorado for the first-ever Rebel Run 5k! Run, walk or stroll to show your passion for Colorado's climate, air, land, water and communities. Create or join a team, or go solo – every dollar you donate or raise supports Conservation Colorado's efforts to protect the beautiful state we love and the communities who […]

  • Eltuck Valley 12K

    Lory Summer Trail Series
    Lory State Park 708 Lodgepole Dr, Bellvue, CO, United States

    Join us each Tuesday evening in August for a fun series of shorter midweek trail races. Our goal is to offer a fun, low-key series of races designed to give newer trail runners an opportunity to dip their toes into the trail racing waters, and to offer more experienced trail racers a chance to sharpen […]

    $25
  • Rock Hawk Trail Race

    Phillip S. Miller Park 1375 West Plum Creek Pkwy, Castle Rock, CO, United States

    Held on the gorgeous, thrilling and rolling trails of Castle Rock’s Miller Park & Ridgeline Trail systems. While not overly technical, these trails will challenge and excite, as you soak up the amazing views. This is an excellent race for both first-time and veteran trail runners, and provides a nice test for those who are […]

  • Boulder Sunset Triathlon

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

    Summer may be coming to an end, but our tri season is still heating up! Join us at the Boulder Reservoir for the 13th Annual Boulder Sunset Triathlon, a local favorite. For the 5th year in a row we are the proud host of the Mountain Collegiate Conference race and the USAT Duathlon Race Series. […]

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