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 […]
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.
Bear Chase Trail Race
Bear Creek Lake Park 15600 W Morrison Rd, Lakewood, CO, United StatesThe Bear Chase Race Endurance Festival is a 100K, 50 Mile, 50K, Half Marathon and the Baby Bear 10K trail race at beautiful Bear Creek Lake Park, in Lakewood, CO. Ultra races on Saturday, short trail races on Sunday An excellent race for first time trail and ultramarathoners, runners will experience a variety of challenging […]
Ghosts & Goblins 5K/10K
City Park Pavilion - Denver 2001 Steele St, Denver, CO, United StatesThe Ghosts & Goblins 5K/10K is a family, friendly event to celebrate the upcoming holiday season. Start your holiday traditions with a fun morning of fitness and friends by joining us at Denver’s City Park. Runners and walkers will complete a timed 5K course through the park, then enjoy a finisher’s medal, a fun vendor […]
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 […]
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