Event details subject to change. Please confirm all information via event website.
Boulder Sunset Triathlon
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. […]
RexRun 5K for PAWSitivity
The RexRun 5K is a 5K run/walk to spread mental health awareness and #PAWSitivity in schools with the help of more Therapy K-9's like Arapahoe County Sheriff's Office K-9 Rex. This year's event is at Dove Valley Park in Centennial on August 6th.
Boulder Sunset 5K/10K
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.
Thirsty 13 Half Marahton
It's a race. It's a Brewfest. It's the Thirsty 13 Half Marathon! Are you thirsty for gorgeous scenery? You won't find a course more beautiful than this one. With the majestic La Plata mountains in the background, you'll cruise through the lush pastures of Wildcat Canyon and past the pristine waters of Lake Nighthorse. This […]
RMRR Fall Marathon Training Series
Riverwalk Ballfields 9830 Riverdale Rd, Thornton, CO, United StatesRMRR’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
Prairie Sky Park 10249 Ridgegate Circle, Lone Tree, CO, United StatesThe 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
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.
Cirque Series 14K
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 […]
Labor Day Half Marathon
Celebrate 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.
Lakewood Trail Running Series II
Bear Creek Lake Park 15600 W Morrison Rd, Lakewood, CO, United StatesThe 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.
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