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