High Lonesome 100

County Road 321 Nathrop, CO, United States

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.

Aspen Valley Marathon

Lions Park 101 Midland Ave, Basalt, CO, United States

Mark your calendars – Don’t miss out on this exhilarating race through the stunning landscapes of Aspen, Colorado! Join us for a one-of-a-kind experience that you’ll cherish forever. The Aspen Valley Marathon takes place in the heart of the Rocky Mountains. The marathon is a Boston Marathon qualifier, offering runners the opportunity to qualify for […]

Audi Power of Four Trail Race

Aspen Mountain 601 East Dean Street, Aspen, CO, United States

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 designed to test the limits and skills of both elite and recreational athletes. The event’s signature race is a challenging 50K Ultra is part of […]

Silverton Alpine Marathon

Memorial Park - Silverton 1800 Greene St, Silverton, CO, United States

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 Howardsville, Eureka, Animas Forks & Gladstone. High point is 12,930 ft atop California Pass. Low point is Silverton at 9,318ft. Total vertical gain is 3,800 […]

Kids’ TRY-athlon

H2O'Brien Pool 10795 Victorian Dr, Parker, CO, United States

This event is all about fun over competition. Boys and girls of all ability levels show their skills in three events: swimming, biking and running. Come on, kids, TRY it out!  Ages: 6 to 12, based on event date Event Distances 6-7 years: 25m swim (1 length)/ 0.75 mile bike/ .5 mile run 8-10 years: 50m […]

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 one eventful day. Take in the natural beauty of the mountain backdrop that sets the scene for this iconic race destination. Most of the bike […]

Spring Creek Memorial Trail Run

Spring Creek Trailhead Steamboat Springs, CO, United States

This 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 remind all of us the importance of sharing multi-purpose use trails. The race is held on the beautiful Spring Creek trail with wildflowers and Aspen […]

Firecracker Flight

Carpenter Park 3498 E 112th Ave, Thornton, CO, United States

Join us for the annual Firecracker 4 & 8 mile! A patriotic-themed event that is perfect for the whole family.

Barr Trail Mountain Race

Cog Railway/Barr Trail 515 Ruxton Ave, Manitou Springs, CO, United States

The Barr Trail Mountain Race is one of the Front Range’s historic summer mountain running events. The 12.6-mile course begins at the Cog Railway Station (6,570 ft) in Manitou Springs, Colorado, ascends Pikes Peak’s iconic Barr Trail to Barr Camp (10,200 ft) before turning, descending and finishing at the Barr Trailhead. The Barr Trail Mountain Race is […]

Donor Dash

Washington Park - Denver 701 S Franklin St, Denver, CO, United States

A 5km Run/Walk to honor, recognize, and celebrate those whose lives have been touched by organ donation.

$17 – $60

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