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

  • Dog Days of Summer 5K

    Dawson Park 1899 Harvard St, Longmont, CO, United States

    Come join us for a race around the entirety of beautiful Lake McIntosh! This 3.5 mile race is a half paved/half dirt course surrounded by wonderful mountain views, vast farmlands, and beautiful aquatic wildlife! Gather at Dawson Neighborhood park near the pirate ship playground where you will find an assortment of vendors, music, games, and […]

  • Strides For Change

    Sloan's Lake Park 1700 Utica Street, Denver, CO, United States

    Join us on August 8th, 2025 at Sloan’s Lake for Strides for Change – a 5K for Youth Mental Health, presented by Resolute Counseling Center. This community-centered event is more than a race — it’s a movement to support and uplift the mental health of our youth. Hosted by Resolute Counseling Center, whose mission is to […]

  • Summer Sizzler 5K

    Cottonwood Creek Park 3920 Dublin Blvd, Colorado Springs, CO, United States

    Join us for the annual Summer Sizzler!  Whether you are looking to run, walk or just enjoy the race SWAG this race is a sure thing for a great time and an incredible experience! This is a fun, family event for all ages with all distances!

  • 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 […]

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