Event details subject to change. Please confirm all information via event website.
Erie Half & 5K
Join us for the Erie Half and 5k! The Hometown Race Series features half marathons and 5k distance events in outlying communities outside the Denver and Boulder metro areas. LOOK […]
Outdoor Divas Triathlon
The Outdoor Divas Sprint Triathlon on August 21st, annually awarded best women's event in Colorado by Competitor Magazine, is the all women's triathlon you've been waiting for! We intentionally keep […]
Race for Research 5K
HOW THE RACE 4 RESEARCH STARTED Michele Plachy-Rubin was a young wife, mother, and kindergarten teacher in the Denver Public Schools when she was diagnosed with brain cancer in December […]
Leadville Trail 10K
Leadville 124 E. Sixth Street, Leadville, CO, United StatesThis out-and-back course uses the first and last 3.1 miles of the LT100 Run course, featuring paved and dirt roads. Held the weekend of the historic Leadville Trail 100 MTB, […]
Into the Hills Eltuck 5K
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 […]
La Garita 200
The La Garita 200 is Southern Colorado’s brand new 200 mile race held in the amazing La Garita mountains. The course consists of a giant loop starting in finishing and […]
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, […]
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 […]
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 […]
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 […]
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 […]
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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