Event details subject to change. Please confirm all information via event website.
Mighty Marmot Kids Trail Race #3
Come join the Vail Recreation District for the 3rd Annual Mighty Marmot Kids Trail Race Series! Youths ages 4 to 10 are welcome to participate. Chose between 1 or 2 miles* to compete amongst your friends and celebrate with awards and ice cream after you finish! *4-year-olds can only race in the 1 mile category This series includes […]
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.
Big Waves 5K
Hi Friends of Big Waves! We are looking forward to having everyone back for our family 5k this year! We are going to do a superhero theme, so come dressed as your favorite good-doer! We will be back at Lifetime Fitness in Westminster (off 144th an I-25). Please reach out if you have any questions […]
CSU Homecoming 5K
The Homecoming Race will take place on the Oval for our traditional course. All ages and abilities are welcome. Proceeds from the Homecoming Race benefit the ongoing research efforts and outreach engagements offered by the Department of Health and Exercise Science. HES is committed to a life-altering education for every one of our 1,400 undergraduate […]
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.
Cart to Cart Trail Run
10 or 19 mile trail runs at the height of fall colors in Crested Butte. Fun prizes to winners and random participants. https://www.cbmountainrunners.org
Mines Homecoming 5K
Campus is gearing up for a Helluva Homecoming and we can’t wait to welcome you back! Check out the Homecoming schedule to see everything happening throughout the weekend.
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 […]
Lafayette Music Fest 5K/10K
Lafayette Music Fest is put on by Rock for the People, a 501(c)(3) nonprofit organization in Lafayette, CO with the mission of building an inclusive live music community by offering free and low-cost rehearsals and recording to musicians from historically underrepresented groups. Because there’s nothing more fun than playing in a band, and your life […]
Ethiorado 5K
Join us this fall for a community 5K Run/Walk in Aurora, CO — a fun, family-friendly event open to runners, walkers, and everyone in between! Whether you’re chasing a personal best or just looking to enjoy a morning outdoors with family and friends, this race is for you. This event is hosted by Ethio-Family Soccer & […]
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 […]
Rut Run 5K
With the Fall Season, Estes Park shines in colors and wilderness experiences! Herds of Elk begin to roam the meadows and open fields; while sounds of bugling Bull Elk call out their territory. Join us as we acknowledge this unique season at the RUT RUN 5K as part of ‘ELK FEST’. Kick starting the weekend of […]
I Can 5K
You CAN 5k. This event is for EVERY ONE. EVERY BODY. You won't get lost. You won't get forgotten. You'll run a clearly marked 5k loop with multiple portojohns & aid stations along the way. And if you're up for a 10k you'll be running the same loop one more time! We're going to keep […]
Miner Gold Rush 5K
Prospect Ridge Academy is thrilled to present our Annual Miner Gold Rush and Fall Festival! All proceeds will benefit Prospect Ridge Academy, a public charter school providing a rigorous, quality K-12 education with an intensified math and science focus. Help support the school while having fun in this exciting community event!
Mustang Music 5K
5K DETAILS: The 5K features a chip-timed race designed to show the beauty of the neighborhoods by Kinard Middle School. Enjoy the music along the course provided by the Kinard and Fossil Ridge bands. REVERSE PARADE/FUN RUN DETAILS: Perfect for young children and non-runners, the Reverse Parade is a Fun Run in which participants will […]
Miles for Moms
Join us at the FloCrit campus and surrounding neighborhoods in southwest Denver for the Annual Miles for Moms Run/Walk/Roll! Lace up your running shoes for a fantastic 3-mile fundraiser run, where we celebrate the triumphs of the amazing teen mothers we support. A welcome and kick-off program will start off the event, followed by the […]
FAMpoint5K
Join us for FAMpoint5K: The Race for the Rest of Us on Saturday, October 3, 2026 at 2:00 p.m. at the Western Colorado Botanical Gardens. we are so excited to bring back one of our favorite fundraisers and return FAMpoint5K to the heart of what it was always meant to be: a short, silly, donut-fueled […]
Grace Race 5K
Help eRace World Hunger at Rainbow Trail Lutheran Camp’s Annual Grace Race! This annual 5k run/walk was started as part of RTLC’s 50th anniversary in 2007, to raise money for ELCA World Hunger. The event is held in collaboration with the Rocky Mountain Synod Hunger Network. Over the last 15 years, RTLC and the participants […]
Hot Chocolate 15K/10K/5K
Start and finish at Civic Center Park amongst Denver's biggest chocolate aficionados. All participants receive a technical running quarter zip with registration. Runners can also enjoy hot chocolate, chocolate fondue, and dipping snacks at the post-race party! It’s not just a race, it’s an experience. Register today!
Windsor Marathon
Welcome to the annual Windsor CO Race! This year's event will start and end at The Island at Pelican Lakes in Water Valley, with a great after party including beer, music and live entertainment! New to the series is a Full Marathon distance, as well as the Half Marathon and Heavy 10K.
Run Crazy Horse Marathon
The Run Crazy Horse Marathon events begin in the shadow of the world's largest mountain carving, Crazy Horse Memorial, and finishes in the heart of the Black Hills... Hill City, South Dakota
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