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

  • Rocky Mountain 5K

    Stanley Park 380 Community Dr, Estes Park, CO, United States

    Escape to the mountains for some fresh air! With the Rocky Mountain Half Marathon, 5K, and Elk Double (half marathon + 5K) you can choose your own adventure! The Rocky Mountain Half Marathon and 5K courses both take place just outside Rocky Mountain National Park and start and end by the lake at the fairgrounds […]

  • Dirty Dozen Trail 10K

    VIX Ranch Park 627 North Wildhorse Dr, New Castle, CO, United States

    The New Castle Rides and Reggae Festival is a celebration of trail running, mountain biking, music and community. Join them for the Dirty Dozen Tail 10K on August 6th.

  • 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 […]

  • Emerald Mountain Epic

    Howelson Hill Steamboat Springs, CO, United States

    The Emerald Mountain Epic presented by Hard Headed attracts some of the nation's best mountain bike and trail running racers, while still offering incredible opportunities for athletes of all skill levels to test their meddle.  Our race is a uniquely rewarding and challenging experience in that it is 90% singletrack with major elevation gains.  To […]

  • Rocky Mountain Half Marathon

    Stanley Park 380 Community Dr, Estes Park, CO, United States

    Escape to the mountains for some fresh air! With the Rocky Mountain Half Marathon, 5K, and Elk Double (half marathon + 5K) you can choose your own adventure! The Rocky Mountain Half Marathon and 5K courses both take place just outside Rocky Mountain National Park and start and end by the lake at the fairgrounds […]

  • Popsicle 5K

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

    What better way to end these HOT summer days than with a Popsicle 5K, AND WE'VE ADDED A 10K & HALF MARATHON?!! Come join us for a 5K, 10K, or half and finish with nice cold popsicles Cottonwood Creek Park!  The course will be an out and back on the Cottonwood Creek Trail.  Come on […]

  • Reece’s Roundup 5K/10K

    Phillip S. Miller Park 1375 West Plum Creek Pkwy, Castle Rock, CO, United States

    Join the Rubino Family at Philip S Miller Park in Castle Rock on August 14th for the 16th Annual Reece’s Roundup 5K/10K. This event supports Reece Rubino in his fight against Spinal Muscular Atrophy.

    $40
  • All-Out Runapalozza

    Apex Center 13150 W 72nd Ave, Arvada, CO, United States

    As those summer mornings are just beginning to cool, join us for a celebration to end the season and our 11th Annual Runapalooza! From the award winning Apex Center, these 5K, 10K & Half Marathon courses will run west along the 2020 Best of the Best Ralston Creek Trail through Arvada's open spaces and stunning golf […]

  • 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 […]

  • Run for the Ring 5K

    Barbara Davis Center for Diabetes 1775 Aurora Ct., Aurora, CO, United States

    he Guild of the Children’s Diabetes Foundation hosts the 11th Annual Run for the Ring 5K Run/Walk and Kids Fun Run, bringing together the type 1 diabetes community and supporters for a morning of fun, movement, and impact. The event will take place on Saturday, August 2, 2025, starting and finishing at the Barbara Davis […]

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