Event details subject to change. Please confirm all information via event website.
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 […]
Rocky Mountain 5K
In partnership with the YMCA Pikes Peak Region, we want to bring you the annual Rocky Mountain Run, the Rocky Mountain State Games official 5k! Athletes will be looped around […]
Nebraska State Fair Marathon
The Nebraska State Fair Marathon will include several different races for the entire family. The races include a Marathon, Half-Marathon, Relay Marathon, 5K, 1-Mile Kid Run, Push Rim Wheelchair, and […]
Historic Main Street 5K
Join us for this family-friendly event! The 5K run/walk will begin and end on Elizabeth’s historic Main Street, featuring a new and exciting course that crosses the reconstructed trail bridge […]
Run Like The Wind 5K
Come race in the mountain town of Allenspark Colorado. Run the scenic 5K that circles through downtown and along dirt roads amid pine forest, boasting awe inspiring views of Mount […]
Summit UP Run
We're bringing back our Summit UP Run presented by Mammut during Union Peak Festival weekend with spectacular views to jump-start your Saturday morning before relaxing and listening to music! Choose from a […]
Run for Hope 5K
This year will mark our 3rd annual Run For Hope when we remember, honor, and celebrate those who lost their lives to addiction. This year's event is hosted by our […]
Ouray 50 Mile
A 50 That's More Difficult Than Your Last 100 How do you build a 50 miler that hits harder than most 100 milers? Easy. Start with a stout mountain hundred […]
Glow and Roll 5K
Glow & Roll is an inclusive, dusk-time 5K Walk/Run/Roll (with a 1.6-mile option). A glow-filled, twilight experience with lights, music and day-glow swag that transforms the event into a celebration […]
Louisville Fall Splash & Dash
Get ready for a fun, energetic racing experience! The event features an indoor swim in the Louisville Rec Center pool, followed by a run on the outdoor trail. This series […]
Wine Run 5K
Join us on Sunday, August 30, 2026 for an exciting annual event that features the amazing scenery and landscape of The Winery At Holy Cross Abbey! Due to the huge […]
Raising the Barr Ultra
Introducing the Raising the Barr Ultra Race. Try to finish as many 10 mile loops around the lake in the first 4 or 10 hours and then switch to 1 […]
Lakewood Trail Running Series I
Bear Creek Lake Park 15600 W Morrison Rd, Lakewood, CO, United StatesThe popular trail running series in Bear Creek Lake Park takes place weekly in September. Different routes allow participants to explore all areas of the park. Racers can compete against […]
Roost Rebellion Relays
Welcome to the Roost Rebellion Relays! Assemble your fastest 4 x 1 mile relay team to race in Washington Park. Each team needs to be co-ed with at least 2 […]
Front Range Ultra Dayze
Welcome to Front Range Ultra Dayze! 100 hours of ultra-running madness! Our goal is to bring people from all over the U.S. together for a festival of ultra-running in Loveland, […]
Grand Traverse Mountain Run
The Grand Traverse Mountain Run is a point-to-point ultra marathon from Crested Butte to Aspen, Colorado. The course follows the route of the Grand Traverse Backcountry Ski race. In total, […]
The Beaver Run
The Beaver Run is a high-altitude mountain running event held Labor Day Weekend in beautiful Breckenridge, Colorado. Participants can choose from 5K and 10K distances along Breckenridge's scenic paved recreation […]
Recovery Run of the Rockies 5K
Join us for the 4th Annual Recovery Run of the Rockies 5K on Saturday, September 5, 2026, at Fossil Creek Park in Fort Collins, Colorado! This professionally timed 5K brings […]
Golden Harvest Half Marathon
5k/10k/Half Marathon registration includes a custom bib, designer shirt, and a custom finisher medal! 1 Mile registration is untimed and includes a custom bib, designer shirt, and a custom finisher […]
Break Your Neck 5K
Come join us to celebrate the access/disability community and raise money for spinal cord injury rehabilitation and awareness. My name is Kenny White III. On November 15 of last year, […]
Creede Mountain Run
The Race Is On! The Creede Mountain Run, established in 1987, celebrates the end of summer and the beginning of fall in our small historic mountain town. This event offers […]
Cirque Series 14K
The race begins at 10,780' ft, starting at the base of Arapahoe Basin, Mountain Goat Plaza, head up to the High Noon parking lot, then to last chance. You will […]
Demon Dash 5K
Lace up your shoes and join us for the Demon Dash at its new course at the NAAC! We're excited to bring this course its new home and onto dirt! […]
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