Timberview Trail Run

Lory State Park 708 Lodgepole Dr, Bellvue, CO, United States

Crisp morning air and a summer sunrise in Colorado. YES PLEASE! Join us on the foothills at Lory State Park for a fun & beautiful morning trail race. This run […]

$20 – $50

Leadville Trail Marathon

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

Run through the historic mining district’s challenging old mining roads and trails, and hit a high of 13,185 feet at Mosquito Pass during the Leadville Trail Marathon or Heavy Half […]

Pride 5K

Civic Center Park 101 14th Avenue, Denver, CO, United States

The Denver PRIDE 5K enables supporters of The Center on Colfax to raise funds in support of our mission. We provide critically important programs and services to Colorado’s LGBTQ community. 100% of each dollar raised […]

Boulder Sunrise Triathlon

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

Join us in celebrating the start of summer in the triathlon capital of the country, Boulder, CO. An athlete favorite with its breath-taking sunrise swim, fast bike and smooth run […]

Boulder Sunrise 5K/10K

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

The Boulder Sunrise 10k & 5k Run has a reputation of being one of the most scenic courses around. BBSC will provide runners with a supported course, including plenty of […]

Chase the Moon Trail Race

Mountain Vista High School 10585 Mountain Vista Ridge, Highlands Ranch, CO, United States

Chase 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 […]

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 […]

Boulder Rez Marathon

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

The 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 […]

Rocky Mountain Tri-Fest

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

Rocky 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, […]

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 […]

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