Chase the Moon Trail Race
Mountain Vista High School 10585 Mountain Vista Ridge, Highlands Ranch, CO, United StatesChase the Moon is a 12-hour team relay and solo ultramarathon, run overnight under the light of the full moon in the Highlands Ranch Backcountry trail system (we promise some of the best views of the metro and front range). Run as a solo ultrarunner, or get your fellow moon-chasing friends for a 3-person or […]
Tri Boulder
Boulder Reservoir 5565 N 51st St, Boulder, CO, United States‘The Beast’ Long Course distance will be back for its second year! As one of Colorado’s most popular summer triathlons, Tri Boulder offers many different multisport race distances, all in one eventful day. Take in the natural beauty of the mountain backdrop that sets the scene for this iconic race destination. Most of the bike […]
Boulder Rez Marathon
Boulder Reservoir 5565 N 51st St, Boulder, CO, United StatesThe 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 […]
PPRR Nielson Challenge
North Monument Valley Park 1794 Culebra Ave., Colorado Springs, CO, United StatesRace 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 […]
PPRR Nielson Challenge
North Monument Valley Park 1794 Culebra Ave., Colorado Springs, CO, United StatesRace 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 […]
Rocky Mountain Tri-Fest
Boulder Reservoir 5565 N 51st St, Boulder, CO, United StatesRocky Mountain Tri-Fest is Colorado's newest Multisport event, catering to the whole family. With events for everyone from mom and dad looking to try their hand at a gravel triathlon, to children looking to do their first triathlon. The Sprint and Super Sprint gravel Tris are beginner friendly with the bike course on the gravel […]
Boulder Sunset Triathlon
Boulder Reservoir 5565 N 51st St, Boulder, CO, United StatesSummer 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 StatesThe 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.
Grand Traverse Mountain Run
Mt. Crested Butte Mt. Crested Butte Ski Resort, Crested Butte, CO, United StatesThe 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.
Labor Day Half Marathon
Salisbury Park 11920 N Motsenbocker Rd, Parker, CO, United StatesCelebrate the last blast of summer at the Labor Day Half Marathon. Sweat your socks off and let summer have its last hooray at Parker's Salisbury Park just a few miles southeast of Denver. There's a distance to meet every taste with a half marathon 10K and 5K.
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