High Lonesome 100
County Road 321 Nathrop, CO, United StatesThe 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.
Chase the Moon Trail Race
Mountain Vista High School 10585 Mountain Vista Ridge, Highlands Ranch, CO, United StatesChase the Moon is a 12-hour team relay and solo ultramarathon, run overnight under the light of the full moon in the Highlands Ranch Backcountry trail system (we promise some […]
Audi Power of Four Trail Race
Aspen Mountain 601 East Dean Street, Aspen, CO, United StatesThe 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 […]
Summer Sizzler 5K/10K/15K
America the Beautiful Park Cimino Dr, Colorado Springs, CO, United StatesJoin us on July 15th, 2023 for the annual Summer Sizzler, featuring the amazing scenery of America the Beautiful Park! Whether you are looking to run, walk or just enjoy […]
Tri Boulder
Boulder Reservoir 5565 N 51st St, Boulder, CO, United States‘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 […]
Heritage Eagles 5K
Heritage High School 1401 W Geddes Ave, Littleton, CO, United StatesSupport the Heritage Eagles cross country team at the annual Heritage Eagles 5K. Last year's race, raised over $3,500 for the Heritage Eagles xc team; $ 10.00 of every registration […]
Spring Creek Memorial Trail Run
Spring Creek Trailhead Steamboat Springs, CO, United StatesThis race is held in memory of Patty Brenner Hagberg who was struck and killed by a truck along the lower part of the trail in 1991. This race should […]
Canceled Fox on the Run Trail Races
Turkey Springs Guard Station US Forest Service Road 629, Pagosa Springs, CO, United StatesThe Fox on the Run is a 10 mile and 5 mile trail race that starts and finishes near the Turkey Springs Guard Station in Pagosa Springs, CO. This 5 mile and 10 mile trail race takes place on July 16th.
Pioneer Days 5K
Jack Dempsey Park 412 Main St, Manassa, CO, United StatesCome join 500 of your running friends for southern Colorado's oldest and perhaps largest road race. This 5K starts and ends near Jack Dempsey Park. After the race, stick around […]
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