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

  • Steamboat Lake Sprint Triathlon

    Steamboat Lake State Park 61105 RCR 129, Clark, CO, United States

    After last summer this event instantly became a personal favorite for our staff, volunteers, and athletes - come find out why!  We couldn't be more excited about this course, this lake, and the overall experience.  The swim starts out in the surprisingly warm waters of Steamboat Lake (74 degrees average race temp), then athletes transition […]

    $85 – $135
  • Backcountry Marathon

    Rio Grande Park Aspen, CO, United States

    Utilizing the beautiful trails that surround Aspen, and now offering three distances - 50K, marathon and heavy half-marathon, all of which run almost exclusively on dirt trails. For the first time in 2025, Aravaipa is introducing an ultra distance that will follow the marathon course and include an out and back to the McNamara Hut […]

  • Sheep Mountain Ultras

    Town of Fairplay Beach Beech Rd, Fairplay, CO, United States

    Make no mistake, the elevation profile for The Sheep Mountain 50 mile and 50k are docile looking. However, the average elevation of over 10,500’ and copious amounts of aggressive terrain, will see you waddle away from this race in shock. Come ready my friends, this mountain throws everything it has at runners, challenging you from […]

  • 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 […]

  • 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

    Boulder Stroke & Stride IX

    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 […]

  • RMRR Trophy Series

    CMRA/RMRR 5K

    deKoevend Park 6315 S. University Blvd., Centennial, CO, United States

    Join us for the August Trophy Series race and picnic at deKoevend Park in Centennial.  This year our friends with the Colorado Masters will be joining us again for a great race and a fun post-race picnic!! We will be providing soda, seltzer, and chips. We ask that you bring your own picnic fare. We […]

  • 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 […]

  • Highlands Ranch Race Series

    HRCA Splash Mash Dash Kid’s Triathlon

    Recreation Center at Northridge 8801 Broadway, Highlands Ranch, CO, United States

    The Splash Mash Dash Kids Triathlon is the perfect for kiddos looking for a way to "TRI" the sport of triathlon or tune up their skills for a larger race. The race will offer kids a safe and fun environment for racing. To encourage participation and enjoyment for all, The Splash Mash Dash Kids Triathlon […]

  • South Suburban Race Series

    Pancake Stampede 5K

    Hudson Gardens and Event Center 6115 S Santa Fe Dr, Littleton, CO, United States

    Work up an appetite for a deluxe breakfast at The Pancake Stampede 5K on August 15th! The race is a part of Littleton's Western Welcome Week celebration and held before the annual pancake breakfast at Geneva Park. The 5K takes place at Hudson Gardens.

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