Event details subject to change. Please confirm all information via event website.
Rocky Mountain Tri-Fest
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 […]
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 PR chasers, a relaxed Hot Lap for walkers and joggers, and a Kid's only version of the half mile Hot Lap for tadpoles ready 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, strollers, dogs!) 9:15- Competitive Waves Begin (10 person waves from slowest to fastest seed times) *All registered participants will receive a performance race tank with original […]
Summit Trail Running Series V
Carter Park 500 South High Street, Breckenridge, CO, United StatesExplore the trails of Breckenridge this summer with the 23rd annual Summit Trail Running Series with each race followed by a post-race party! The Series consists of 5 trail races in and around Summit County, May-July. Each race features a short and long course, and all races are open to runners of all abilities ages […]
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 most stunning and rugged terrain with breathtaking views of the Colorado Trail, Engineer Mountain, Wilson group of 14ers, Lizard Head, and many other incredible peaks […]
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 terrain, and long stretches with little flat relief. The 50K includes over 5,000 feet of elevation gain. The 50M includes over 9,000 feet of elevation […]
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 in its 12th year, Westminster Trail Race continues to be one of the Front Range’s most approachable and scenic trail events. The courses wind along […]
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 is supported by sponsorships from businesses and individuals, over 400 race participants nationwide, 100 plus volunteers, and a dedicated race committee offering their time and […]
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 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 […]
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 engagement, and fun. This election-year event is an opportunity to connect with neighbors, learn about candidates and issues on the ballot, and celebrate the importance […]
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 school - 'Building Leaders'.
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 family and dog-friendly 5K race along the Rio Grande Trail benefitting the shelter pets of Colorado Animal Rescue (C.A.R.E.). Whether you're trotting alongside your pup […]
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 support Teacher Innovation Grants for students with special needs. These grants are awarded to teachers who have innovative ideas to enhance learning for students. Help […]
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 follows the classic Backyard Ultra format where runners complete a 4.167 mile loop every hour, on the hour, until only one runner remains. If you […]
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 race will consist of 5: 1k loops with each loop beginning and ending at the Daylight Donuts parking lot. Each racer will have to finish […]
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 Awareness, Treatment & Research. It's more than a walk/run - come connect with your local migraine & headache community, listen to our speakers & visit sponsors […]
Just Peachy 5K
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 families and beginners, but also a very fast course for those looking to PR.
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 to get the season going! We are excited to give the community the opportunity to contribute to the program and race on campus. Please register […]
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 natural lake, and past historic landmarks for one of the most unique races you'll ever experience! The race starts and ends at the Grand Lake […]
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 through vibrant color stations while supporting a great cause. All proceeds benefit Colorado West Christian School students and programs. Whether you’re in it for fun, […]
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 UP! At the Erie event, we often see the early morning skies with dotted with delightfully colorful hot-air balloons. Whatever distance you're ready to tackle, […]
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 the race cap low at 600 women to create a fun, festive, yet intimate racing environment. Great goodie bags, one of our biggest expos of […]
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 of 1996. The Race 4 Research was conceived in 1997 by Michele's friends to raise money to fund local cancer research. Michele was able to […]
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 the same place with only a small section of a few miles of out and back to connect. Starting in beautiful South Fork,CO on the […]
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, runners navigate old mining roads, singletrack and alpine tundra over mountain passes, exposed ridgelines, and high summits. TMR is extremely difficult with big elevation gain […]
Leadville Trail 100
Leadville 124 E. Sixth Street, Leadville, CO, United StatesThe legendary “Race Across The Sky” 100-mile run is where it all started back in 1983. This is it. The race where legends are created and limits are tested. One hundred miles of extreme Colorado Rockies terrain — from elevations of 9,200 to 12,600 feet. You will give the mountain respect, and earn respect from […]
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.
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