Boulder Stroke & Stride VII

Boulder Reservoir 5565 N 51st St, Boulder, CO, United States

The Boulder Stroke & Stride enters its 23rd season in 2024, and offers Boulder area athletes a fun 1-lap 750 Meter Swim, or 2-Lap 1500 Meter swim in Boulder Reservoir, followed by a 5k run on the reservoir dam on 8 Thursday evenings (plus one Wednesday evening) throughout the summer. Many participants make their open-water […]

BRR Summer Track Series #3

Potts Field 4001 Discovery Drive, Boulder, CO, United States

Join us for The Boulder Road Runners All-Comers Summer Track & Field series! We are back at CU Pott’s Field on a brand new track!! Fun for all, from newcomers of any age racing for the first time to veteran competitors looking to test their fitness, all in a friendly, welcoming environment. We host multiple […]

$10 – $15

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.

Chase the Moon Trail Race

Mountain Vista High School 10585 Mountain Vista Ridge, Highlands Ranch, CO, United States

Chase 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 of the best views of the metro and front range). Run as a solo ultrarunner, or get your fellow moon-chasing friends for a 3-person or […]

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 […]

Summer Sizzler 5K/10K/15K

America the Beautiful Park Cimino Dr, Colorado Springs, CO, United States

Join 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 the race SWAG this race is a sure thing for a great time and an incredible experience! This is a fun, family event for all […]

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 […]

Heritage Eagles 5K

Heritage High School 1401 W Geddes Ave, Littleton, CO, United States

Support 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 goes right back to supporting the team. New this year, all-you-can-eat pancake breakfast provided by Flippin' Flapjacks. The Liberty Bell Cross Country Invitational has been […]

Event Series Vail Trail Running Series

Vail 10K and 5K @10,000 Feet

Vail Village 292 E Meadow Dr, Vail, CO, United States

Both Dynafit 5K and 10K races, presented by Summit Ford, will begin at 8 a.m. at the top of Gondola One at Mid-Vail on Vail Mountain, with the entire race taking place above 9,000 feet. The average grade of the 10K is 7 percent with an elevation gain of nearly 1,200 feet, while the shorter […]

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