Event details subject to change. Please confirm all information via event website.
Bullfrog Summer Surge
The Bullfrog Summer Surge is a community first race morning built around movement, connection, and summer fun. Set at Addenbrooke Park, there's something for every pace: a timed 5K for […]
Berkeley Circuit
Event Description Berkeley Circuit Race Schedule: 8:30- Free and Fun Kids Quarter Mile (no registration necessary, just show up to race!) 8:45- Community One Mile Run (all paces welcome- walkers, […]
San Juan Softie 100
The softest 100 miler in the San Juans This 100 mile ultra marathon starts and finishes just north of Durango, Colorado. The race will take you through some of the […]
Weld County Commissioner’s Cup
This is a private event for Weld County employees and their families. The race is not open to the general public. Sorry!
Roxborough Ultras
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
Wayne Carle Middle School 10020 100th Ave, Westminster, CO, United StatesAfter 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
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
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
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
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.
Dash for Democracy 5K
Dash for Democracy is the Denver Democrats' 5th Annual 5K Run / 2K Walk, taking place at City Park and bringing together community members for a morning of fitness, civic […]
Frontier Academy Community 5K
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 […]
Dog Day 5K
Join us at Two Rivers Park in Glenwood Springs on Saturday, August 15 for a morning full of wagging tails, fresh air, and community spirit! The Dog Day 5K is a […]
Sunrise Stampede 5K
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
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 […]
Police Department Donut 5K
Come join the Yuma Police department for a fun 5k to raise money for our Scholarship fund. This 5k will partner with the police departments favorite snacks Daylight Donuts. The […]
Miles for Migraine 5K
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 […]
Grizzly 2 Mile
Every year TRXC hosts a race to begin the season and celebrate ThunderRidge High School Cross Country. This season we will be holding a Grizzly 2-mile on the ThunderRidge campus […]
Buffalo Run 5K
Held during Grand Lake's iconic Buffalo Days weekend, the Buffalo Run 5k route passes through the charming town of Grand Lake, along the scenic shores of Colorado's highest and deepest […]
CWCS 5K Color Run
Join us for the annual Colorado West Christian School 5K Color Fun Run—a fun, family-friendly race along the scenic river trail at Riverbottom Park in Montrose, Colorado. Run or walk […]
Erie Half & 5K
Join us for the Erie Half and 5k! The Hometown Race Series features half marathons and 5k distance events in outlying communities outside the Denver and Boulder metro areas. LOOK […]
Outdoor Divas Triathlon
The Outdoor Divas Sprint Triathlon on August 21st, annually awarded best women's event in Colorado by Competitor Magazine, is the all women's triathlon you've been waiting for! We intentionally keep […]
Race for Research 5K
HOW THE RACE 4 RESEARCH STARTED Michele Plachy-Rubin was a young wife, mother, and kindergarten teacher in the Denver Public Schools when she was diagnosed with brain cancer in December […]
La Garita 200
The La Garita 200 is Southern Colorado’s brand new 200 mile race held in the amazing La Garita mountains. The course consists of a giant loop starting in finishing and […]
Telluride Mountain Run
The Telluride Mountain Run is a challenging and technical race in the San Juan Mountains above the beautiful historic mining town of Telluride, Colorado. With five challenging and technical routes, […]
Staunton Rocks! Trail Marathon
Welcome to the Staunton Rocks! Marathon & Half Marathon, an event put on by trail runners for trail runners on August 28, 2021. Touring the renowned singletrack of Staunton State Park in Colorado’s Front Range Mountains southwest of Denver, the race will take you back in time as you glide by historic buildings and old milling operations.
Impact Uganda 5K/10K
Our annual 5K/10K Run or Walk to Support Susie's Higher-Ed Fund We'll be returning to Family Worship Center for the start and finish of this year's 5K/10K. Our event will […]
Coyote Chase 5K
The Coyote Chase 5k is a 5k race that supports the Monarch HS XC program. The race is on the Monarch HS campus and is a 2k loop that consists […]
Mountain Swim Series IV
Highest altitude organized marathon swim event in the country at ~8,000 feet. RACE DETAILS Distance Price* Swimmers 2.5K $110.00 Both skin/wetsuit event options 1-hour swim cutoff** 1 loop around […]
Ram Run 5K
Come join in the celebration of the resurgence of a great community event. The Ram Run will be returning to it's traditional month. This fun and exciting event will include […]
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