Event details subject to change. Please confirm all information via event website.
Run For Your Flapjacks 5K
Enjoy the first weekend of fall with a breathtaking workout overlooking the waters of Stagecoach State Park Reservoir then savor warm cider with a delicious stack of flapjacks hot off the grill.
Deep Creek Trail Half Marathon
This spectacular trail run will start at the beginning of Last Dollar Road by the Telluride Airport. Racers will make their way down Last Dollar Road to the Deep Creek Corral. At the corral the singletrack starts and racers will enter the Aspen-filled woods lining the deep creek trail on their journey back to the […]
Night Nation Run
The Night Nation Run is the World’s first Running Music Festival the ultimate blend of a Music Festival and a Fun Run. Experience a music filled course with Live DJs, Bubble Zones, Light Shows, Neon and Black Lights! Cross the finish line into an Epic Main Stage After Party featuring Top Headliner DJs! To date, over 1.5 MILLION people […]
RMRR Fall Marathon Training Series #3
Riverwalk Ballfields 9830 Riverdale Rd, Thornton, CO, United StatesRMRR’s Marathon Training Series provides 10M and 20M races that are low cost, friendly, fully supported, and officially timed. All you need to do is focus on your running! Our races fit perfectly in training schedules for Colfax, Boston, New York, Chicago, and other full and half marathons. Everyone is welcome at our MTS races: RMRR members, […]
Sawatch Ascent 50K
Built to showcase the stunning beauty of the Sawatch Range, this high alpine and vert-heavy 50K will challenge and inspire you in equal measure! From starting under the shadow of Mount Princeton and the endless miles of buttery, aspen shaded Colorado Trail singletrack, to the awe-inspiring high point of 13,150ft and panoramic views of Colorado’s highest range, you will get to experience the wonders of the Sawatch over 33 miles and 7,000ft of vertical gain.
Boulderthon
Run one of the fastest-growing, top-rated marathons in the country! After nearly tripling in size and selling out last year, Boulderthon has instituted a new 5,000 runner cap and is expected to sell out again this year. Run a 5k, 10k, Half, or Full, at the foothills of the Rockies, in the stunning running mecca […]
Last Call Triathlon
Yes! I want ONE MORE adventure!! Escape to the lake! The Last Call Triathlon will be an event you’ll look forward to all season long. Why? Beautiful mountain views, great weather and a family fun venue! Did we mention camping? Yup! There’s that too. Sitting on the east side of Loveland and southeast of Fort Collins, […]
Pat Mahan Memorial 5K
Join us for the Pat Mahan Memorial 5K in Wiggins, Colorado, a family-friendly event celebrating the life and legacy of Pat Mahan. Lace up your running shoes and hit the course with us as we raise funds to support local students through the Pat Mahan Memorial Foundation, which provides scholarships to graduating seniors at Wiggins […]
Colorado Coyotes Youth XC Invitational
Join us for the annual Colorado Coyotes Cross Country Invitational. This meet is open to all youth runners between the ages of 6-14 years old. The course is a mix of mostly grass and crushed dirt rock with a few sidewalk crossings and a few hills. The Invitational will be professionally chip timed by Colorado […]
Flyin’ Lion 5K
The Flyin' Lion 5K returns this year to raise money to support Littleton High School’s Lions Sports Booster Club, a non-profit 501c3 made up of parent volunteers and school administrators. The race will take place at Littleton High School on October 2nd, 2022.
Run With the Wolves 5K
Join us for WWE's Annual 'Run with the Wolves'! Run with the Wolves is a 5k Run and 1k Fun Run/Walk that raises money for West Woods Elementary PTSA. It is a positive, healthy community event that gets your blood pumping while supporting your school. All proceeds from the race are granted back to the […]
Stego Stampede
The first-ever Stego Stampede over Dinosaur Ridge in Morrison, Colorado is a fun run (2 miles) for all ages (and dogs on leash) where costumes are encouraged and prizes will be awarded for best dressed, most team spirit, etc. This event highlights the dinosaur fossils embedded in Cretaceous and Jurassic sandstone layers along the paved […]
14er Fest 14K and 5K
5K: Grab some of the family or friends and join us for this 3.1-mile fun run and race! The race starts and ends right in the heart of vendor village. You'll run on road, dirt and gravel trails during this race as you wind through the Buena Vista Riverpark. You'll get some of the best […]
Oktoberfest 5K
WestCo Brewing 905 Struthers Ave, Grand Junction, CO, United StatesPut on your lederhosen and sneakers as we celebrate fall with a family-friendly, fun-filled morning. The course along the beautiful riverfront path is perfect for all ability levels, from first-time 5K participants to seasoned runners, walkers, kids, parents with strollers, and even your furry friends. Afterward, enjoy festive oompah music, a cold stein and a […]
Greenland Pack Burro Race
Welcome to the annual Greenland Open Space Pack Burro Races presented by Double Rainbow Ranch! Grab your burro and join us for a fun and rewarding day on the majestic Greenland Open Space Trail in beautiful Larkspur, Colorado. RACE RULES Each entrant will pay a fee as determined by the Race Director for each race. […]
Lions Roar 5K
Lions Roar 5K is a family friendly 5K to support Leawood Elementary School PTSA! We welcome all ages and abilities. Our race takes place at beautiful Clement Park in Littleton, Colorado which is right in our neighborhood. Money earned at this race will go towards technology fees for our students' Chromebooks, school beautification and our […]
Joy & Justice 5K
Join us for the Race for Joy & Justice 5K, a family-friendly run/walk event benefiting the Joy & Justice organization based in Timnath, Colorado. This exciting event brings together people of all ages and abilities to support Joy & Justice’s mission of providing experiences of joy for women and children recovering from domestic violence while […]
Bear Chase Trail Race
The Bear Chase Race Endurance Festival is a 100K, 50 Mile, 50K, Half Marathon, Baby Bear 10K and 5K trail race at beautiful Bear Creek Lake Park, in Lakewood, CO. Ultra races on Saturday, short trail races on Sunday An excellent race for first time trail and ultramarathoners, runners will experience a variety of challenging […]
Arches Marathon
Started in 2004 as a fall companion to the popular Canyonlands Half Marathon, Arches Half Marathon has hosted many runners on the road course. In 2021, Arches became a trail event. The new course features beautiful red rock formations, views of the snow covered La Sal Mountains and the awe inspiring Behind the Rocks Wilderness […]
Colorado Springs Marathon
Join us for the 13th Annual Colorado Springs Marathon on Saturday, October 3, 2026! Whether you're a seasoned runner or taking on your first 5K, we have four exciting race options to choose from. Each course highlights the stunning beauty of Colorado Springs—winding past historic landmarks, through scenic parks, and finishing downtown at the Colorado […]
Above the Clouds Ultra
Experience the amazing Colorado fall colors, fast and flowing singletrack of Rampart Reservoir and the spectacular sweeping views of America’s Mountain, Pikes Peak, in the inaugural Above the Clouds Ultra!
West Elk Trail Marathon
The West Elk Challenge is a point-to-point trail marathon (with a 30K option) through Western Colorado’s North Fork Valley and West Elk Mountains at peak fall colors. But it’s also something bigger: 100% of proceeds fund scholarships for Nature Connection’s summer camps. This race is built around a simple idea: courage grows through challenge — especially […]
Castle Rock Trail Festival
Welcome to the Town of Castle Rock’s epic trail event. Come to challenge yourself on the vast ridgeline trail system and enjoy Castle Rock’s local trails. Trail run options range from the liveBIG 5K to the Ultra Marathon 50K. If you’ve run this trail system before, you know these are some beautiful and beguiling trails. […]
Taco Bell 50K
It has been described as Urban Legend. More mysterious and barking spiders than the Barkley Marathons. The International Taco Bell 50k boasts a higher DNF rate than the famed Leadville 100 Trail Race. As the tale is told, the race began with a hot tub, a stoic Russian, a short king from New York, and […]
Rim to Rim Royal Gorge Run
Get ready for a ROYALly GORGEous experience! Whether you’re tackling the 5K, the 8-mile trail run, or the half marathon trail run, this event offers something truly special. All three races feature the exhilarating opportunity to run across America’s highest suspension bridge, the iconic Royal Gorge Bridge, with breathtaking views of one of Colorado’s most […]
Sage Burner Trail Race
Nestled in the Rocky Mountains, about 2 hours east of Grand Junction and 3 hours west of Denver, lies a small running jewel called Gunnison, Colorado. Visit Gunnison, and you’ll be treated to some of the best outdoor recreation this planet has to offer.
Spooky Sprint Half Marathon
Join us for the annual Spooky Sprint 5k/10k & Half Marathon! A fun, Halloween-themed event that is perfect for the whole family.
Grand Valley Backyard Ultra
This is a true last-man-standing event, and it will go until there is only one runner left, no matter how long it takes. Unlike all other competition race formats, this one isn’t about speed. It’s about grit, determination, and pure will to finish another lap. When you’ve had enough and don’t think you can finish […]
Outlast Denver
OUTLAST is a 6-hour trail endurance challenge where runners complete a 5K every hour, on the hour. Each lap must be finished within the hour to stay in the event. If you finish early, you rest until the next round. Miss a lap, and you’re out. Complete all six rounds, and you OUTLAST. This isn't […]
The Pretzel Run
Oktoberfest in Colorado!! Owned and managed by a Bavarian Race Director.... The Annual PRETZEL RUN will move 8 blocks down to Louisville Community Park for a LARGER BIER GARDEN, LIVE MUSIK and 4 Trail Races. Hlaf Marathon, 10k, 5k and Kids Mile. (Allows more room for the race) and the park will allow for a […]
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