Event details subject to change. Please confirm all information via event website.
CMRA Elk Meadow Trail Run
Come up to scenic Elk Meadow Open Space for an exhilarating 5.1 mile trail run. This is a timed event that starts and ends near the Lewis Ridge Trail Head.
Grin & Bear It Trail Race
The Grin & Bear It is Crested Butte’s oldest trail challenge. Historically presented as a sprint to Green Lake and back, this classic event has evolved to offer a 25k […]
Estes Park Backyard Ultra
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 Peak Triathlon
The Boulder Peak Triathlon, Duathlon & Aquabike on July 10th is one of the countries longest and most well-known triathlons. For the veteran or first time racer, this is THE […]
High Lonesome 100
The High Lonesome 100 is a high flying endurance race in the Sawatch range of the Colorado Rocky Mountains. With 22,500' of vertical gain and reaching an elevation of 13,150', it's a hell of a course. The race runs in a loop through some of the most beautiful single track in the state, and takes runners on the Continental Divide and Colorado Trail, through 2 ghost towns, over 5 alpine passes, through remote basins, and over soaring ridges. This year's event takes place on July 30th.
Audi Power of Four Trail Race
The Audi Power of Four Race Series is a premier endurance race series utilizing the unique and amazing terrain of each of the four Aspen Snowmass mountains. Each race is […]
Summer Splash Prairie Dog Half Marathon
Castle View High School 5254 N. Meadows Dr., Castle Rock, CO, United StatesWelcome to the Summer Splash Prairie Dog Half, 10k & 5k in Castle Rock, Colorado. Part of the Prairie Dog Half race series, join us in July as we race […]
Silverton Alpine Marathon
Experience the best of the San Juan Mountains with an 8 miler, a marathon, or a 50 kilometer run along the Alpine Loop past the historic mining ghost towns of […]
Tri Boulder
‘The Beast’ Long Course distance will be back for its second year! As one of Colorado’s most popular summer triathlons, Tri Boulder offers many different multisport race distances, all in […]
Gastro-Dash 10K
The Berthoud Gastro-Dash 10K is not just a footrace; it’s an epic, hilarious test of both speed and stomach, challenging runners to tackle a 6.2-mile course punctuated by mandatory food […]
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