Event details subject to change. Please confirm all information via event website.
Telluride Mountain Run
The Telluride Mountain Run is a challenging and technical race in the San Juan Mountains above the beautiful historic mining town of Telluride, Colorado. With five challenging and technical routes, […]
Leadville Trail 100
Leadville 124 E. Sixth Street, Leadville, CO, United StatesThe legendary “Race Across The Sky” 100-mile run is where it all started back in 1983. This is it. The race where legends are created and limits are tested. One […]
Staunton Rocks! Trail Marathon
Welcome to the Staunton Rocks! Marathon & Half Marathon, an event put on by trail runners for trail runners on August 28, 2021. Touring the renowned singletrack of Staunton State Park in Colorado’s Front Range Mountains southwest of Denver, the race will take you back in time as you glide by historic buildings and old milling operations.
Bergen Peak Half Marathon
Buchanan Park Recreation Center 32003 Ellingwood Trail, Evergreen, CO, United StatesCome run with us in beautiful Evergreen to the top of Bergen Peak at gorgeous Elk Meadow Park! This race day will offer both a 5k and a half marathon […]
Impact Uganda 5K/10K
Our annual 5K/10K Run or Walk to Support Susie's Higher-Ed Fund We'll be returning to Family Worship Center for the start and finish of this year's 5K/10K. Our event will […]
Byers Peak Stampede
High Country Stampede Rodeo 1741 Co Hwy 73, Winter Park, CO, United StatesThe race is hosted by Shining Stars Foundation, a nonprofit providing recreational and social programs for children and families affected by pediatric cancer. All proceeds support the kids. There is […]
Arrowhead Half Marathon
The Vail Recreation District is excited to announce a NEW venue for one of our favorite events in the 2021 Dynafit Vail Trail Running Series - The Dynafit Half Marathon and 5K at Arrowhead in Beaver Creek on August 21st.
Coyote Chase 5K
The Coyote Chase 5k is a 5k race that supports the Monarch HS XC program. The race is on the Monarch HS campus and is a 2k loop that consists […]
Mountain Swim Series IV
Highest altitude organized marathon swim event in the country at ~8,000 feet. RACE DETAILS Distance Price* Swimmers 2.5K $110.00 Both skin/wetsuit event options 1-hour swim cutoff** 1 loop around […]
Gunni Hi Tri
This Sprint Triathlon is proudly brought to you by the Gunnison Parks & Recreation Department. It begins with a 500yard swim (10 laps) at the Community & Aquatics Center, then […]
Ram Run 5K
Come join in the celebration of the resurgence of a great community event. The Ram Run will be returning to it's traditional month. This fun and exciting event will include […]
Unite for Bleeding Disorders Walk
Sunlight Showdown 10K
Sunlight Mountain Resort 10901 County Road 117, Glenwood Springs, CO, United StatesWelcome to the Sunlight Mountain Race Series, where mountain air, winding trails, and a vibrant community come together for an unforgettable summer of running. For seven years, our half marathon […]
Antelope Dash Trail Race
Nestled in the foothills of the Laramie Mountains, Curt Gowdy State Park offers a hidden gem of a trail system. The Antelope Dash takes runners through a stunning landscape of […]
Warrior Waterfront 5K
Come join us for the Warrior Waterfront 5k. This 5k will be run in conjunction with the Central High School Warrior Cross Country Invitational and all proceeds will go to […]
Jog in the Bog 5K
Now in its 28th year, the Jog in the Bog 5K is a fun opportunity to get active while supporting SLHS. Registration includes a commemorative t-shirt, goodie bag, entry into […]
Boulder 5K Taco Run
Super charge your Taco Crushing appetite with a run before the Boulder Taco Fest! A non-competitive fun run on some of Boulder’s most beautiful multi-use paths. There’s even an aid […]
Pioneer Prairie Dog Half Marathon
Westminster Promenade 10600 Westminster Blvd, Westminster, CO, United StatesWelcome to the Pioneer Prairie Dog Half Marathon event; the one that started the series! With 10k and 5k events too! Everyone is back to school and slipping into a […]
Rebel Run 5K
Be part of something bigger at Conservation Colorado’s second annual Rebel Run 5K — where movement meets momentum for our climate, air, land, water and communities. Last year, more than 230 […]
Log Hill Hustle 5K/10K
Join us for the Annual Log Hill Hustle 5K & 10K, a scenic fun run/walk hosted by Fortuna Tierra Club in support of local education. Set against the stunning backdrop […]
Central Park Kids Triathlon
Wellington Swim-Run Challenge
Swimmers may choose to swim with their shoes, paddles, a wetsuit, pull buoy, floaties, rubber duckies, inflatable flamingoes or any other nonmotorized swim aid in this event. Race Course Per […]
PH in the Park
2026 marks 17 years of community, awareness, and fundraising to support people with pulmonary hypertension. The University of Colorado Denver, Children’s Hospital Colorado, and the Pulmonary Hypertension Association invite you […]
Cooldown Denver
Eltuck Valley 12K
Lory State Park 708 Lodgepole Dr, Bellvue, CO, United StatesJoin us each Tuesday evening in August for a fun series of shorter midweek trail races. Our goal is to offer a fun, low-key series of races designed to give […]
Continental Divide Trail Run
Steamboat Springs Ski Resort 2305 Mt Werner Cir, Steamboat Springs, CO, United StatesDistances: 50k (9 hour cutoff) and 16 mile (7 hour cutoff) and 5 mile (New!)
Rock Hawk Trail Race
Held on the gorgeous, thrilling and rolling trails of Castle Rock’s Miller Park & Ridgeline Trail systems. While not overly technical, these trails will challenge and excite, as you soak […]
Boulder Sunset Triathlon
Summer may be coming to an end, but our tri season is still heating up! Join us at the Boulder Reservoir for the 13th Annual Boulder Sunset Triathlon, a local […]
YMCA of Pueblo Indoor Triathlon
Take on the challenge of the YMCA of Pueblo Indoor Triathlon, a fun, beginner-friendly event that combines swimming, cycling, and running in a supportive environment! Participants will complete a 10-minute […]
Waneka Classic Community 5K
A free, timed 5K, open to the public, held prior to the Centaurus Cross Country Invitational. Proceeds from the World Famous Concessions Stand and T-shirt sales benefit the Centaurus Cross […]
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