Event details subject to change. Please confirm all information via event website.
Ugly Sweater 5K
Get into the holiday spirit with the Ugly Sweater 5K! Runners and walkers, young and old, are invited to join us at Washington Park in Denver for a flat, fast […]
Resolution Run 5K
Run out the old year, and welcome the new! Now in its 42nd year, the Resolution Run is a family-friendly, neighborhood streets 5K starting & finishing at the Edora Pool […]
Rescue Run
Welcome back to Norris-Penrose Events Center / Bear Creek Park! Back in the beginning... The Rescue Run Start/Finish was at Norris-Penrose Events Center - After many wonderful years at Palmer […]
Resolute Runner 5K
The Resolute Runner 5K is the KICK OFF PARTY OF THE YEAR! It's time to be RESOLUTE, to retroactively earn your pumpkin pie and chocolate truffles, and to start the […]
Hot Chocolate 5K
Warm up your taste buds because you’re invited to the very first Hot Chocolate 5k Run! Come run your personal record and enjoy some post-race treats. This race is the […]
Polar Bear 5K
You run faster when it's cold, right? Come Run for the 🥶Chill of it...all the "cool" runners are doing it! RACE HIGHLIGHTS 🛍️Participants get some super fantastic running socks! 📸FREE […]
Chilly Cheeks Winter Duathlon
Cherry Creek State Park 4201 S Parker Rd, Aurora, CO, United StatesThe Chilly Cheeks Duathlon Series is now a stand-alone event held in late February. The 63rd Chilly Cheeks Duathlon will be held in the traditional format of Run-Bike-Run. Both runs […]
Runnin’ of the Green Lucky 7K
Feeling the luck o' the Irish? Lace-up and chase the rainbow in Denver’s favorite Irish-themed run! Join us at Washington Park for some shenanigans! Runnin' of the Green (ROTG) is […]
Three Creeks Half Marathon
Racing Underground brings you an amazing half marathon this spring! The Three Creeks Half Marathon features a half marathon course that is flat, fast and scenic! Travel on foot through […]
Mountain Ridge Trail Race
Mountain Ridge takes place near Highlands Ranch primarily on the Douglas County East-West Regional Trail. This gently rolling course will keep the Heart Rate pumping while offering some of the […]
Platte River Half Marathon
Denver's oldest half marathon runs along the Platte River Trail, covering parts of Littleton and Denver.
Rattler Trail Race
Rattler was created to feature one of Colorado Springs' best city parks, Palmer Park. Runners will enjoy views of the city and Pikes Peak from the sandstone bluffs, while running […]
Royal Gorge Groove Trail Runs
Prepare for some fun in Cañon City! Enjoy scenic views along the rim of the Royal Gorge, 900 feet above the Arkansas River. All races will start/finish at the Royal […]
Greenland Trail Race
The Greenland Trail Race offers four outstanding distances in southern Douglas County. Run the 4 Miler, the 8 Miler, the 25K, or tackle the 50K ultramarathon, Colorado’s fastest 50K! With Pikes Peak as your backdrop, you’ll cruise over a soft dirt trail on your way to a new personal best. With chip timing, an innovative technical running shirt in men’s and women’s sizing, food and beer at the finish, this race will make you want to come back for more!
Colorado Marathon
Marathon, Half Marathon, 10k, 5k and 3-Person Marathon Relay. Marathon, Marathon Relay and Half Marathon runners get to run down the scenic, downhill Poudre Canyon to the finish in Old […]
Wine Run 5K
Like Running or Walking? Love Wine? This race is for you! Join us on Saturday, May 8, 2027 at 9:30am and 11:00am (you will pick your start time during registration) […]
Ram Party Trail Runs
With plenty of race options for everybody centered around the beautiful Rampart Reservoir in Woodland Park, Colorado, you're sure to have a good time while you take in the epic […]
North Fork Trail Race
The North Fork 50 Mile/50K is 100% trails, mainly single track and some double track, starting and finishing along lovely Buffalo Creek, in the mountains about 50 miles southwest of […]
Barr Lake Trail Race
The Barr Lake Trail Race returns to Brighton, CO, offering beautiful lake views and a prime opportunity for new PRs. Now in its sixth year, this event features our flattest […]
Colorado Triathlon
The Colorado Triathlon is where Colorado comes to race! The Colorado Triathlon - sprint & olympic distances, duathlon & aquabike options . To make this the "can't miss" event of […]
Lory Off-Road Triathlon
XTERRA Lory Triathlon is the perfect kick-off to the year for the seasoned off-road triathlete, or a great opportunity for the road triathlete wanting to try out a mountain bike […]
Ring the Springs Trail Races
Get ready for an unforgettable adventure at Ring the Springs trail running races in the stunning Colorado Springs, Colorado! This thrilling event showcases the area's incredible natural beauty, with a […]
Boulder Peak Triathlon
The Boulder Peak Triathlon, Duathlon & Aquabike on July 10th is one of the countries longest and most well-known triathlons. For the veteran or first time racer, this is THE […]
Silverton Alpine Marathon
Experience the best of the San Juan Mountains with an 8 miler, a marathon, or a 50 kilometer run along the Alpine Loop past the historic mining ghost towns of […]
Kendall Mountain Run
Meet the mountain this summer in Silverton, Colorado! The Kendall Mountain Run starts in downtown Silverton and traverses jeep roads to within a final 300 vertical foot scramble to the […]
Steamboat Lake Triathlon
After last summer this event instantly became a personal favorite for our staff, volunteers, and athletes - come find out why! We couldn't be more excited about this course, this […]
Backcountry Marathon
Utilizing the beautiful trails that surround Aspen, and now offering three distances - 50K, marathon and heavy half-marathon, all of which run almost exclusively on dirt trails. For the first […]
Stagecoach Gravel Triathlon
We didn't get the chance to launch this race in 2020, but that didn't diminish our passion for this brand new style of triathlon! To say this race is “unique” […]
Westminster Trail Race
Wayne Carle Middle School 10020 100th Ave, Westminster, CO, United StatesAfter a special night edition last year, Westminster returns to its traditional daytime format in 2026 — bringing runners back to a classic morning on the trails at Standley Lake. […]
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 […]
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