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

  • Ouray 50 Mile

    Fellin Park 1001 US-550, Ouray, CO, United States

    A 50 That's More Difficult Than Your Last 100 How do you build a 50 miler that hits harder than most 100 milers? Easy. Start with a stout mountain hundred miler. Anything with ~24k feet of climbing should do. Find 50 miles of flat and discard it. Add copious amounts of highly-technical, unforgiving, why-would-they-even-think-this-is-a-good-idea trails. […]

  • RMRR Fall Marathon Training Series

    Riverwalk Ballfields 9830 Riverdale Rd, Thornton, CO, United States

    RMRR’s Marathon Training Series provides 10M and 20M races that are low cost, friendly, fully supported, and officially timed.  All you need to do is focus on your running!  Our races fit perfectly in training schedules for Colfax, Boston, New York, Chicago, and other full and half marathons. Everyone is welcome at our MTS races:  RMRR members, […]

  • 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.

  • Wine Run 5K

    The Winery At Holy Cross Abbey 3011 US-50, Canon City, CO

    Join us on Sunday, August 30, 2026 for an exciting annual event that features the amazing scenery and landscape of The Winery At Holy Cross Abbey! Due to the huge turnout, we will have 2 start times for the event (9:30am and 11am). You'll select a start time when you sign up. Since July 2002, […]

    $35
  • Lakewood Trail Running Series I

    Lakewood Trail Running Series
    Bear Creek Lake Park 15600 W Morrison Rd, Lakewood, CO, United States

    The popular trail running series in Bear Creek Lake Park takes place weekly in September. Different routes allow participants to explore all areas of the park. Racers can compete against others in-person on Wednesday evenings, or run the marked course on their own Tuesday-Thursday weekly for a virtual option.

    $55 – $70
  • 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 […]

  • Golden Harvest Half Marathon

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

    5k/10k/Half Marathon 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, and a […]

  • Creede Mountain Run

    Creede Historical Society Museum & Library 15 S Main St, Creede, CO, United States

    The Race Is On! The Creede Mountain Run, established in 1987, celebrates the end of summer and the beginning of fall in our small historic mountain town. This event offers participants the opportunity to enjoy the breathtaking San Juan Mountains in Colorado on a 2, 12, 22 mile, or 50K course! The race begins within […]

  • Cirque Series 14K

    Arapahoe Basin Ski Resort 28194 US-6, Keystone, CO, United States

    The race begins at 10,780' ft, starting at the base of Arapahoe Basin, Mountain Goat Plaza, head up to the High Noon parking lot, then to last chance.  You will cross highway 6, get on the A-Basin summer road.  You will follow the summer road up to Black Mountain Lodge.  From Black Mountain Lodge you […]

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