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

  • 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 […]

  • 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.

  • Grand Traverse Mountain Run

    Mt. Crested Butte Mt. Crested Butte Ski Resort, Crested Butte, CO, United States

    The Grand Traverse Mountain Run is a point-to-point ultra marathon from Crested Butte to Aspen, Colorado. The course follows the route of the Grand Traverse Backcountry Ski race. In total, runners travel 40 miles across the Elk Mountains with over 6,000′ of elevation gain.

  • Littlefoot Sprint Triathlon

    Bear Creek Lake Park 15600 W Morrison Rd, Lakewood, CO, United States

    Enjoy a fun late season tri at beautiful Bear Creek Lake Park in a land before time. Set at the base of the foothills, the Littlefoot Triathlon starts off with a 750 meter swim in Big Soda Lake, with water temps expected to be approximately 70 degrees. Next, a rolling 15K bike ride on smooth […]

  • Harvest Moon Long Course Triathlon

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

    The Harvest Moon Triathlon the 23rd edition of this event takes place at the beautiful Boulder Reservoir on September 10th, 2022.  Est. in 2000 this Colorado classic  provides the veterans to beginners a challenging, affordable, and competitive race with a local flavor.  Whether this is your final event of the season, or a tune-up for […]

  • Spirit of the Valley Run

    St. Matthew's Episcopal Church 3888 27 1/2 Road, Grand Junction, CO, United States

    Helping to Heal! The Spirit of the Valley Run, Walk 'N Roll 1K and 5K timed races are set for Saturday September 9, 2023. Runners, walkers and rollers are all welcome for a great morning of competition, fun, food, and rock ‘n roll. The race will benefit two local organizations - the VA Recreational Therapy […]

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