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

  • Stagecoach Gravel Triathlon

    Stagecoach Reservoir 25500 Co Rd 14, Oak Creek, CO, United States

    We didn't get the chance to launch this race in 2020, but that didn't diminish our passion for this brand new style of triathlon!  To say this race is “unique” would be an understatement! Limited to just 250 athletes, we're excited to announce the first ever gravel triathlon to the Colorado triathlon landscape! This event […]

  • Boulder Stroke & Stride IX

    Boulder Stroke & Stride
    Boulder Reservoir 5565 N 51st St, Boulder, CO, United States

    The Boulder Stroke & Stride offers Boulder area athletes a fun 1-lap 750 Meter Swim, or 2-Lap 1500 Meter swim in Boulder Reservoir, followed by a 5k run on the reservoir dam. Stroke & Stride happens weekly on Thursday nights throughout the Summer from June 4th to August 6th WITH THE EXCEPTION OF Thursday June […]

  • Rocky Mountain Tri-Fest

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

    Rocky Mountain Tri-Fest is Colorado's newest Multisport event, catering to the whole family. With events for everyone from mom and dad looking to try their hand at a gravel triathlon, to children looking to do their first triathlon. The Sprint and Super Sprint gravel Tris are beginner friendly with the bike course on the gravel […]

  • Outdoor Divas Triathlon

    Union Reservoir 461 County Road 26, Longmont, CO, United States

    The Outdoor Divas Sprint Triathlon on August 21st, annually awarded best women's event in Colorado by Competitor Magazine, is the all women's triathlon you've been waiting for!  We intentionally keep the race cap low at 600 women to create a fun, festive, yet intimate racing environment.  Great goodie bags, one of our biggest expos of […]

  • Leadville Trail 100

    Leadville Race Series
    Leadville 124 E. Sixth Street, Leadville, CO, United States

    The legendary “Race Across The Sky” 100-mile run is where it all started back in 1983. This is it. The race where legends are created and limits are tested. One hundred miles of extreme Colorado Rockies terrain — from elevations of 9,200 to 12,600 feet. You will give the mountain respect, and earn respect from […]

  • Pioneer Prairie Dog Half Marathon

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

    Get out to enjoy the crisp autumn air at the Pioneer Prairie Dog Half & 5k/10k! We will be celebrating autumn at the Start/Finish line located at the beautiful Westminster Promenade Terrace. Each participant will receive a Gender Specific Tech Tee to commemorate the day and half marathoners will receive a Finisher Medal! Stick around […]

    $35 – $80
  • 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. […]

  • Boulder Sunset 5K/10K

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

    The Boulder Sunset 10K & 5K Run is part of BBSC’s biggest endurance event of the summer. Spend your weekend racing with BBSC at the incredible and scenic Boulder Reservoir. Register, and start training for the end-of-the-summer endurance festival with BBSC.

  • Bluffs 8K Trail Run

    South Suburban Race Series
    Prairie Sky Park 10249 Ridgegate Circle, Lone Tree, CO, United States

    The Bluffs 8K Trail Race has rolling hills and beautiful views as you run or walk through the Bluffs Regional Park. The race will start/finish near the Prairie Sky parking lot o n August 28th.

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