Event details subject to change. Please confirm all information via event website.

Roxborough Ultras

Roxborough State Park 6323 Roxborough Dr, Littleton

Roxborough Ultras is a late-summer trail ultramarathon in Roxborough State Park, Colorado, offering a 50K and 50M on fully marked, all-trail courses. Both distances feature sustained climbing, technical sections, exposed […]

Westminster Trail Race

Endurance Race Series
Wayne Carle Middle School 10020 100th Ave, Westminster

After a special night edition last year, Westminster returns to its traditional daytime format in 2026 — bringing runners back to a classic morning on the trails at Standley Lake.Now […]

Mt Sneffels Half Marathon

Ouray Ouray

The Mt. Sneffels Half-Marathon and Kids Fun Run began 25 years ago. In 2021, the 10 K was added. The Race is the foundation’s major fundraising event of the year.  It […]

Boulder Rez Marathon

Boulder Reservoir 5565 N 51st St, Boulder

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 […]

Cheyenne Mountain Run

Cheyenne Mountain State Park 410 JL Ranch Heights, Colorado Springs

The Cheyenne Mountain Run in Colorado Springs will take place on October 8, 2022 and will feature 3 trail races: a 25K to the top of Cheyenne Mountain for the more advanced trail runner, a 10K for the experienced runners and a 5K trail run for all to enjoy.

Med Bow Rail Marathon

Lake Owen Lake Owen Rd, Albany

The Friends of the Medicine Bow Rail Trail will host the second annual Med Bow Rail Marathon & Half Marathon on August 13th, 2022 at Lake Owen in the Medicine Bow National Forest near Laramie, Wyoming.

$50 – $75

Frontier Academy Community 5K

Twin Rivers Park 1501 65th Avenue, Greeley

The Frontier Academy Community 5K is meant to serve the community of Greeley and the surrounding area. Through this race we hope to fulfill the vision and mission of our […]

$15 – $30

Sunrise Stampede 5K

Silver Creek High School 4901 Nelson Road, Longmont

The Sunrise Stampede 5K with a 1-mile fun run is a family-oriented run/walk that has raised $270,000+ for student programs in the St. Vrain Valley School District.  All net proceeds […]

Wild West Backyard Ultra

Loudy Simpson Park 1009 S Ranney St, Craig

The MOCO Trails Wild West Backyard Ultra is a community-driven endurance event held at beautiful Loudy Simpson Park in Craig, Colorado along the banks of the Yampa River. This race […]

Miles for Migraine 5K

Great Lawn Park 101 Yosemite St, Denver

Miles for Migraine will host its annual 2-mile Walk (or Intentional Movement of your choice), 5K Run and Relax Denver Event. This event is a fundraiser for Migraine & Headache […]

Just Peachy 5K

Palisade Riverbend Park 451 Pendleton St., Palisade

Join the Grand Junction Sports Commission for the Just Peachy 5K presented by Grand Valley Primary Care Palisade (Community Hospital) on Saturday, August 19th.  This fun 5K is great for […]

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