Event details subject to change. Please confirm all information via event website.
CWCS 5K Color Run
Join us for the annual Colorado West Christian School 5K Color Fun Run—a fun, family-friendly race along the scenic river trail at Riverbottom Park in Montrose, Colorado. Run or walk […]
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 […]
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.
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 […]
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
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 […]
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
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 […]
RexRun 5K for PAWSitivity
The RexRun 5K is a 5K run/walk to spread mental health awareness and #PAWSitivity in schools with the help of more Therapy K-9's like Arapahoe County Sheriff's Office K-9 Rex. This year's event is at Dove Valley Park in Centennial on August 6th.
Boulder Sunset 5K/10K
The Boulder Sunset 10K & 5K Run is part of BBSC’s biggest endurance event of the summer. Spend your weekend racing with BBSC at the incredible and scenic Boulder Reservoir. Register, […]
Thirsty 13 Half Marahton
It's a race. It's a Brewfest. It's the Thirsty 13 Half Marathon! Are you thirsty for gorgeous scenery? You won't find a course more beautiful than this one. With the […]
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