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 […]

  • Summit Trail Running Series V

    Summit Trail Running Series
    Carter Park 500 South High Street, Breckenridge, CO, United States

    Explore the trails of Breckenridge this summer with the 23rd annual Summit Trail Running Series with each race followed by a post-race party! The Series consists of 5 trail races in and around Summit County, May-July. Each race features a short and long course, and all races are open to runners of all abilities ages […]

  • San Juan Softie 100

    Durango Nordic Center 49786 Hwy 550 N, Durango, CO, United States

    The softest 100 miler in the San Juans This 100 mile ultra marathon starts and finishes just north of Durango, Colorado. The race will take you through some of the most stunning and rugged terrain with breathtaking views of the Colorado Trail, Engineer Mountain, Wilson group of 14ers, Lizard Head, and many other incredible peaks […]

  • Roxborough Ultras

    Roxborough State Park 6323 Roxborough Dr, Littleton, CO, United States

    Roxborough Ultras is a late-summer trail ultramarathon in Roxborough State Park, Colorado, offering a 50K and 50M on fully marked, all-trail courses. Both distances feature sustained climbing, technical sections, exposed terrain, and long stretches with little flat relief. The 50K includes over 5,000 feet of elevation gain. The 50M includes over 9,000 feet of elevation […]

  • Westminster Trail Race

    Endurance Race Series
    Wayne Carle Middle School 10020 100th Ave, Westminster, CO, United States

    After a special night edition last year, Westminster returns to its traditional daytime format in 2026 — bringing runners back to a classic morning on the trails at Standley Lake.Now in its 12th year, Westminster Trail Race continues to be one of the Front Range’s most approachable and scenic trail events. The courses wind along […]

  • Mt Sneffels Half Marathon

    Ouray Ouray, CO, United States

    The Mt. Sneffels Half-Marathon and Kids Fun Run began 25 years ago. In 2021, the 10 K was added. The Race is the foundation’s major fundraising event of the year.  It is supported by sponsorships from businesses and individuals, over 400 race participants nationwide, 100 plus volunteers, and a dedicated race committee offering their time and […]

  • Boulder Rez Marathon

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

    The Boulder Rez Marathon is quickly becoming a Boulder classic! This isn’t just another run around the lake. September temperatures will create the perfect race atmosphere. BBSC will offer a Marathon, ¾ Marathon, Half Marathon, 10K and relay, guaranteeing the perfect distance for you! This popular course will take runners around the Boulder Reservoir on […]

  • Med Bow Rail Marathon

    Lake Owen Lake Owen Rd, Albany, WY, United States

    The Friends of the Medicine Bow Rail Trail will host the second annual Med Bow Rail Marathon & Half Marathon on August 13th, 2022 at Lake Owen in the Medicine Bow National Forest near Laramie, Wyoming.

    $50 – $75
  • Wild West Backyard Ultra

    Loudy Simpson Park 1009 S Ranney St, Craig, CO, United States

    The MOCO Trails Wild West Backyard Ultra is a community-driven endurance event held at beautiful Loudy Simpson Park in Craig, Colorado along the banks of the Yampa River. This race follows the classic Backyard Ultra format where runners complete a 4.167 mile loop every hour, on the hour, until only one runner remains. If you […]

  • Just Peachy 5K

    Palisade Riverbend Park 451 Pendleton St., Palisade, CO, United States

    Join the Grand Junction Sports Commission for the Just Peachy 5K presented by Grand Valley Primary Care Palisade (Community Hospital) on Saturday, August 19th.  This fun 5K is great for families and beginners, but also a very fast course for those looking to PR.

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