Colorado 13er Half Marathon

Home Depot 1200 Dillon Road Louisville CO 80027, Louisville, CO, United States

The Colorado 13er is THE event where the best parts of trail running and road racing combine to create a truly enjoyable, kind-to-your-body, well-supported 13.1 race! Seasoned runners and first-timers […]

All-Out Summer Breeze

Stenger Soccer Complex 11200 W 58th Ave, Arvada, CO, United States

From the heart of the West Metro area and the Stenger Soccer Complex, All-Out brings you our 11th annual Summer Breeze! Along with its Endless Series sidekick in January Polar […]

Barr Lake Trail Race

Barr Lake State Park 13401 Piccadilly Road, Brighton, CO, United States

The Barr Lake Trail Race returns to Brighton, CO, offering beautiful lake views and a prime opportunity for new PRs. Now in its sixth year, this event features our flattest […]

Ironman 70.3

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

Boulder has been a household name in the world of triathlon for decades. This endurance community has built a reputation among triathletes for training hard, racing fast and enjoying every […]

Father’s Day Classic

Apex Center 13150 W 72nd Ave, Arvada, CO, United States

It's an annual Fathers Day tradition in Arvada! All are welcome - walkers, joggers and speed demons, too! Swag includes t-shirts for ALL participants! There is a 5K and 10K. […]

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 […]

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 […]

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 […]

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