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

  • Georgetown to Idaho Springs Half Marathon

    Georgetown Lake Georgetown Lake Road, Georgetown, CO, United States

    Part of the Colorado Mountain Half + Series, Georgetown to Idaho Springs Half Marathon is a Colorado Runner’s Must-Do. This iconic Half Marathon is one of the most pleasurable races in the western US. The point-to-point course is a scenic and gently rolling downhill mountain course that winds down the Clear Creek Valley -- starting at an […]

    $103.68
  • Human Race Half Marathon

    Civic Center Park - Fort Collins Fort Collins, CO 80521, Fort Collins, CO, United States

    What is better than one day of running? TWO days of running! The Choice City Running Event in Civic Center Park Fort Collins has something for everyone. Kick off a run-filled weekend with the Jane Welzel Mountain Avenue Mile on Friday evening with 1-mile races for everyone including kids, middle & high school students, families, […]

  • Summer Sizzler 5K

    Carpenter Park 3498 E 112th Ave, Thornton, 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! Great Swag - designer shirt & custom medal Chip-timing […]

  • 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 […]

  • 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 […]

  • 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 […]

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