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

  • All-Out Dog Days

    Church Ranch Office Park 10170 Church Ranch Wy, Westminster, CO, United States

    Get ready for some fun in the sun and a great mid-season test of your training as we bring our 11th Annual Dog Days 5K, 10K & Half Marathon! Centrally located between Denver & Boulder along with its Endless Series sidekick in December Fa La La, the beauty of our breathtaking Flatirons as a backdrop will inspire you […]

  • Heatwave Half Marathon

    Westminster Promenade 10600 Westminster Blvd, Westminster, CO, United States

    5K/10K/Half- Marathon & Relay registration includes a custom bib, designer shirt, and a custom finisher medal! 1 Mile registration is untimed and includes a custom bib, designer shirt, and a custom finisher medal! The kid's dash is a fun, untimed dash for our kiddos ages 10 and under. Registration includes a mini bib, youth-sized shirt, […]

  • Stepping Stone 5K

    Clement Park 7306 W. Bowles Avenue, Littleton, CO, United States

    Stepping Stone Support Center and Trailhead Community have come together to present this amazing event to benefit adults with developmental disabilities. Complete two laps of Johnson Reservoir at Clement Park for the 5K or take the cutoff after one lap for the untimed Shortcut.

    $30.00
  • CMRA Elk Meadow Trail Run

    Elk Meadow Park 2855 Bergen Peak Drive, Evergreen, CO, United States

    Come up to scenic Elk Meadow Open Space for an exhilarating 5.1 mile trail run. This is a timed event that starts and ends near the Lewis Ridge Trail Head.

  • Estes Park Backyard Ultra

    Estes Park High School 1600 Manford Ave, Estes Park, CO, United States

    The Backyard Ultra with the views. ​ The Backyard Ultra is a form of Ultra race where runners must complete 4.167 miles in less than one hour, every hour, until only one runner remains to complete a lap. This runner is crowned the winner and only finisher, while all others will be marked as DNF. There is […]

  • Boulder Peak Triathlon

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

    The Boulder Peak Triathlon, Duathlon & Aquabike on July 10th is one of the countries longest and most well-known triathlons.  For the veteran or first time racer, this is THE can’t miss event of the summer triathlon season, and the crown jewel of the Colorado Triathlon Series. Racers are tackling the infamous “Olde Stage” Hill, […]

  • High Lonesome 100

    County Road 321 Nathrop, CO, United States

    The High Lonesome 100 is a high flying endurance race in the Sawatch range of the Colorado Rocky Mountains. With 22,500' of vertical gain and reaching an elevation of 13,150', it's a hell of a course. The race runs in a loop through some of the most beautiful single track in the state, and takes runners on the Continental Divide and Colorado Trail, through 2 ghost towns, over 5 alpine passes, through remote basins, and over soaring ridges. This year's event takes place on July 30th.

  • Audi Power of Four Trail Race

    Aspen Mountain 601 East Dean Street, Aspen, CO, United States

    The Audi Power of Four Race Series is a premier endurance race series utilizing the unique and amazing terrain of each of the four Aspen Snowmass mountains. Each race is designed to test the limits and skills of both elite and recreational athletes. The event’s signature race is a challenging 50K Ultra is part of […]

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