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

  • Erie Half & 5K

    Reliance Park 900 Weld County Road 1.5, Erie, CO, United States

    Join us for the Erie Half and 5k! The Hometown Race Series features half marathons and 5k distance events in outlying communities outside the Denver and Boulder metro areas. LOOK UP! At the Erie event, we often see the early morning skies with dotted with delightfully colorful hot-air balloons. Whatever distance you're ready to tackle, […]

  • Outdoor Divas Triathlon

    Union Reservoir 461 County Road 26, Longmont, CO, United States

    The Outdoor Divas Sprint Triathlon on August 21st, annually awarded best women's event in Colorado by Competitor Magazine, is the all women's triathlon you've been waiting for!  We intentionally keep the race cap low at 600 women to create a fun, festive, yet intimate racing environment.  Great goodie bags, one of our biggest expos of […]

  • Leadville Trail 100

    Leadville Race Series
    Leadville 124 E. Sixth Street, Leadville, CO, United States

    The legendary “Race Across The Sky” 100-mile run is where it all started back in 1983. This is it. The race where legends are created and limits are tested. One hundred miles of extreme Colorado Rockies terrain — from elevations of 9,200 to 12,600 feet. You will give the mountain respect, and earn respect from […]

  • Pioneer Prairie Dog Half Marathon

    Prairie Dog Race Series
    Westminster Promenade 10600 Westminster Blvd, Westminster, CO, United States

    Welcome to the Pioneer Prairie Dog Half Marathon event; the one that started the series! With 10k and 5k events too! Everyone is back to school and slipping into a routine. Make this your mental health break as you break away from the chaos of weekly schedules and give yourself a morning to race in […]

  • Rock Hawk Trail Race

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

    Held on the gorgeous, thrilling and rolling trails of Castle Rock’s Miller Park & Ridgeline Trail systems. While not overly technical, these trails will challenge and excite, as you soak up the amazing views. This is an excellent race for both first-time and veteran trail runners, and provides a nice test for those who are […]

  • Boulder Sunset Triathlon

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

    Summer may be coming to an end, but our tri season is still heating up! Join us at the Boulder Reservoir for the 13th Annual Boulder Sunset Triathlon, a local favorite. For the 5th year in a row we are the proud host of the Mountain Collegiate Conference race and the USAT Duathlon Race Series. […]

  • Boulder Sunset 5K/10K

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

    The Boulder Sunset 10K & 5K Run is part of BBSC’s biggest endurance event of the summer. Spend your weekend racing with BBSC at the incredible and scenic Boulder Reservoir. Register, and start training for the end-of-the-summer endurance festival with BBSC.

  • Bluffs 8K Trail Run

    South Suburban Race Series
    Prairie Sky Park 10249 Ridgegate Circle, Lone Tree, CO, United States

    The Bluffs 8K Trail Race has rolling hills and beautiful views as you run or walk through the Bluffs Regional Park. The race will start/finish near the Prairie Sky parking lot o n August 28th.

  • Grand Traverse Mountain Run

    Mt. Crested Butte Mt. Crested Butte Ski Resort, Crested Butte, CO, United States

    The Grand Traverse Mountain Run is a point-to-point ultra marathon from Crested Butte to Aspen, Colorado. The course follows the route of the Grand Traverse Backcountry Ski race. In total, runners travel 40 miles across the Elk Mountains with over 6,000′ of elevation gain.

  • 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 […]

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