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

  • Cryogenic Cannibal Chase

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

    Planning on some degenerate behavior at Frozen Dead Guy Days? Start your morning off right with an 8k ripper around Lake Estes. This race is the morning pre game for FDGD where you'll score a sick beanie and a hearty breakfast bagel from Village Bagels before the festival kicks off.

  • Equinox Half Marathon

    Sparge Brewing 3999 GW Bush Avenue Unit 101, Wellington, CO, United States

    Both races start & finish at Sparge Brewing in Wellington 3999 GW Bush Unit 101, Wellington, CO 80549

  • Splash & Dash III

    Louisville Recreation and Senior Center 900 Via Appia Way, Louisville, CO, United States

    Join us for a Kids’ Splash & Dash Series this winter at the Louisville Rec Center! Get ready for a fun, energetic winter racing experience! Each event features an indoor swim in the Louisville Rec Center pool, followed by a run on the outdoor trail. In the case of bad weather, the run will move […]

  • Cayson Pearson Memorial 5K

    Green Mountain High School 13175 West Green Mountain Dr, Lakewood, CO, United States

    This annual fun run/walk (& knockout tournament if you also love basketball) is held each year to honor the memory of Cayson Pearson, award scholarships, raise funds for additional and future scholarships, and raise awareness for mental health & suicide prevention.

  • PPRR Nielson Challenge

    PPRR Nielson Challenge

    North Monument Valley Park 1794 Culebra Ave., Colorado Springs, CO, United States

    Race Format The first time you run this event, you'll establish a base time for yourself. This base time is used to generate a handicap time. The handicap time is calculated using an algorithm developed by Bob Royse, and it's geared to favor a beginning runner and the slower runners. Click here for an explanation of the […]

  • Three Creeks Half Marathon

    Cherry Creek State Park 4201 S Parker Rd, Aurora, CO, United States

    Racing Underground brings you an amazing half marathon this spring! The Three Creeks Half Marathon features a half marathon course that is flat, fast and scenic! Travel on foot through some of the most beautiful parts of Cherry Creek State Park, with a total combined elevation gain of only 291 feet spread out over 13.1 […]

  • Desert RATS Trail Running Festival

    Mack Trailhead on Kokopelli Trail 1022 Old US Hwy 6 & 50, Mack, CO, United States

    Desert Rats Trail Running Festival by UTMB has four unique distances, three days of racing and indescribable views of the desert. There is something for every runner. Enjoy views of the Colorado River as you race through flowy singletrack, climb up the mesa, and take in the vastness of the desert.

  • Run the Ranch Trail Runs

    Sylvan Dale Guest Ranch 2939 N CR 31D, Loveland, CO, United States

    For the 5th year running and benefiting the Heart J organization, we are bringing back an amazing and beautiful trail race to Loveland, CO. You will have 6 distances to choose from. Come run on beautiful trails on private land at Sylvan Dale Guest Ranch. The views alone are to die for! There are different […]

  • NoCo Urban Ultra & Relay

    Island Grove Park 501 N 14th Ave, Greeley, CO, United States

    A collaboration event between run.Windsor and Breakaway Athletic Events celebrating the Poudre River Trail. This long-distance race takes you on a sprawling tour of Northern Colorado via the picturesque Poudre River Trail. You'll enjoy scenic views and local amenities through Fort Collins, Timnath, Windsor and Greeley. While ultra distances can be daunting, this race is an ideal option for […]

  • Mountain Ridge Trail Race

    Mountain Ridge Middle School 10590 Mountain Vista Ridge, Highlands Ranch, CO, United States

    Mountain Ridge takes place near Highlands Ranch primarily on the Douglas County East-West Regional Trail. This gently rolling course will keep the Heart Rate pumping while offering some of the best views in the front range. The Mountain Ridge Trail Race will once again start and finish from Mountain Ridge Middle School, and offer 100% […]

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