Event details subject to change. Please confirm all information via event website.
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, […]
Labor Day Half Marathon
Celebrate the last blast of summer at the Labor Day Half Marathon. Sweat your socks off and let summer have its last hooray at Parker's Salisbury Park just a few miles southeast of Denver. There's a distance to meet every taste with a half marathon 10K and 5K.
FCA All Abilities 5K
See the Northern Colorado All-Ability communities come together in faith and sports through FCA All-Abilities. We are running for: Awareness of sports programs for all ages for individuals with disabilities […]
Oak Creek No Fun Run
Oak Creek Town Hall 123 Nancy Crawford Blvd, Oak Creek, CO, United StatesThe Running Series is excited to have the Oak Creek No Fun Run on our schedule again! Please join us in remembering long-time Running Series competitor Larry Brooks, a former […]
Gold Roots Trail Series #4
Courtney Ryley Cooper Park 2350 Colorado Blvd, Idaho Springs, CO, United StatesRun the Mighty ARGO hill this summer in a 4 race series! You will have the option of a short loop (~5 miles, ~750' gain) or a long loop (~9 […]
Lakewood Trail Running Series II
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 […]
American Heroes Run
The tragic events of 9/11/01 changed our nation forever. Let us not forget our proud history and those who fight everyday to keep us free. Please join us for this […]
Flaming Foliage Relay
Flaming Foliage is a 165 mile overnight team relay race adventure with single track trails, from Idaho Springs to beautiful Buena Vista, over Guanella, Georgia & Fremont Passes. Since 2013, […]
Res Hill Ruck 5K
Join us for a 5K on September 11th for a memorial run/ruck through the pine trees on Reservoir Hill with breath taking views of Pagosa Springs. The trail includes just […]
Snow Mountain Ranch Trail Festival
Join us at the YMCA of the Rockies in Granby for the annual Snow Mountain Ranch Trail Running Festival. This event features 4 races with 2 different "challenges". Races will […]
Littlefoot Sprint Triathlon
Enjoy a fun late season tri at beautiful Bear Creek Lake Park in a land before time. Set at the base of the foothills, the Littlefoot Triathlon starts off with […]
Black Squirrel Half Marathon
The Black Squirrel Trail Half Marathon takes place on the wonderful trails of Lory State Park to the northwest of Fort Collins, CO. The trail half marathon course offers a […]
Devil on the Divide 50K/22K
We are pleased to present one of the most beautiful and challenging trail racing events in the state of Colorado with breathtaking (literally and figuratively) views of Clear Creek County […]
5K on the Runway
Run down the Runway at Denver International Airport, one of top 10 busiest airports in the world! Only one other time has DEN shut down a runway for this 5K […]
Lake Nighthorse Triathlon
Scenic and hilly Sprint and Olympic(standard) distance triathlons held at Lake Nighthorse Recreation Area in Durango 9/6/25 with prize money for top 3 overall male and female racers.
CMRA South Seven
The course will be on wide, crushed gravel paths and, depending on the status of construction in the nearby neighborhood, potentially a little bit of single track. It's a hilly, […]
Gleneagle Spirit 5K
The 2025 Gleneagle Spirit 5k is the Fourth annual event held in the Gleneagle community. The event features a 5k Run/Walk for Fun that winds through the streets of the […]
Ned*Ned Half Marathon
Embark on your journey by winding through Old Town Nederland, the epitome of Colorado mountain towns. The Half Marathon will take you on dirt roads and single track trails as […]
Team Hope 5K
The Rocky Mountain Chapter of the Huntington’s Disease Society of America (HDSA) will host the annual Heroes and Villains Team Hope Walk and 5K Run at Stapleton Central Park. Wear […]
Together with Tanzania 5K
Timed 5K for all ages and paces! Mostly flat, lots of shade, winds through a quiet Greenwood Village neighborhood. This certified 5K course begins and ends in our parking lot. […]
Trail Sisters Half Marathon
Come run a Half Marathon or our new 10k that twist and turn through sage brush and ponderosa pines, all while providing stunning views of the Collegiate Peaks. Located in […]
RINO 5K
Take the roads of the RiNo Art District this fall for a fun run or walk through Denver’s most vibrant neighborhood. Sign up for the 5K or 1 mile, or […]
Rattlesnake Rumble Trail Race
Highland Homecoming 5K
Join us for the Annual Highland Homecoming 5k Run & Walk. This race benefits the middle and high school cross-country teams.
Imogene Pass Run
The Imogene Pass Run (IPR) is a 17.1 mile point-to-point mountain race within the western San Juan mountains of Colorado. The course runs along a route which connects the towns […]
Tater Trot 5K
The Colorado Potato Festival will be kicking off at Chapman Park in Monte Vista with the annual Tater Trot 5K. This sponsored event is a great addition to the festival […]
Meadowgold Trail Run
There's No Way They Grew Lettuce Here! The seventh and final race in the Vail Recreation District's Vail Trail Running Series, the MeadowGold 11K & 5K is presented by Town of Minturn. This […]
The Denver 5K
THE Denver 5k! Denver's Iconic Sloan Lake is the setting for the return of 'THE Denver 5k'. Celebrate with friends and family as you race around the lake in the […]
6 Dot Dash
The National Federation of the Blind of Colorado 6 Dot Dash presented by Comcast is an annual 5k event to raise awareness and funds for the National Federation of the […]
Spirit of the Valley Run
Helping to Heal! The Spirit of the Valley Run, Walk 'N Roll 1K and 5K timed races are set for Saturday September 9, 2023. Runners, walkers and rollers are all […]
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