Unicorn 5K

Carpenter Park 3498 E 112th Ave, Thornton, CO, United States

Ready to get off the sofa and gallop around Thornton with some friends?  Yeah, you are!  Come frolic with us at the Unicorn Runner 5k in Thornton to kick off your summer!  You'll earn a sweet tee shirt and a flashy unicorn finisher medal! It's a 5k distance for all, and whether you walk, trot, […]

Estes Park Backyard Ultra

Estes Park High School 1600 Manford Ave, Estes Park, CO, United States

The Backyard Ultra with the views. ​ The Backyard Ultra is a form of Ultra race where runners must complete 4.167 miles in less than one hour, every hour, until only one runner remains to complete a lap. This runner is crowned the winner and only finisher, while all others will be marked as DNF. There is […]

Midsummers Night Run

Winter Park Resort 85 Parsenn Rd, Winter Park, CO, United States

Join us for an evening at Winter Park by participating in our Second Annual Midsummer Night's 10k!  This run will begin and end at the base of Winter Park Resort with an elevation gain of approximately 570 ft.  Enjoy a combination of gravel roads and trails on this run.

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 course, all with the flatirons painted in the background. You’ll never want to race another venue again after this experience! The seasoned race crew led […]

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 aid stations fully stocked and staffed with volunteers. Once you reach the finish line enjoy the post-race party with music, beer, food, and awards! This […]

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 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 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 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 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, 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 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 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. […]

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