Event details subject to change. Please confirm all information via event website.
Great Divide Ultra
Experience the spring-fed meadows, massive rocks of Pikes Peak granite, and sweeping views of Colorado’s most spectacular mountains in the Great Divide Ultras. This Colorado early season 100m, 100k, 50k […]
Mace’s Hideout 100
Mace’s Hideout 100 is as beautiful as it is tough. ONLY 75 spots open for each distance!!! The Wet Mountains of Colorado are a hidden gem set amongst giants. One […]
Colorado 13er
The Colorado 13er is THE event where the best parts of trail running and road racing combine to create a truly enjoyable, kind-to-your-body, well-supported 13.1 race! Seasoned runners and first-timers […]
Crazy Legs 10K
-The race begins at 7:00am and held at Devil’s Backbone Open Space 1725 Hidden Valley Drive in Loveland. Trail conditions can be access through the website https://www.larimer.org/naturalresources/parks/devils-backbone -If the trails […]
Steamboat Marathon
Run alongside the roaring Elk River through the emerald green pastures on Country Road 129 with the snow-capped Rocky Mountains of Colorado all around and find out why the Steamboat […]
Breckenridge Brewery Half Marathon
Breckenridge Brewery - Littleton 2920 Brewery Lane, Littleton, CO, United StatesJoin us for the Breckenridge Brewery Half Marathon & 5k on June 7, 2026. Starting and ending at the Breckenridge Brewery in Littleton, CO. Join us for the Breckenridge Brewery […]
RMRR Bible Park 4K
Bible Park 6802 E Yale Ave, Denver, CO, United StatesEveryone – slow, fast, or in-between – can win at RMRR Trophy Series races. With our handicap scoring system, we predict YOUR finish time based on recent running results, giving you a great […]
Flamingo Day 5K
Join us for a fun and festive day at Denver's Sloan's Lake Park.
Adidas Terrex 10K Spring Runoff
Vail Village 292 E Meadow Dr, Vail, CO, United StatesChallenge the Vail Valley’s best trail runners along with top professionals at almost 9,000 feet as you compete for a cash purse. This course will truly test your fitness with its constant […]
Deadwood Mickelson Trail Marathon
26.2 Miles of Black Hills, South Dakota Beauty!
Adidas Terrex 20K Trail Run
Vail Village 292 E Meadow Dr, Vail, CO, United StatesCOURSE CHANGE FOR 2026 & BIGGER PRIZE PURSE! A behemoth of running races, the adidas TERREX 20K Trail Run is for the boldest competitors. Destroy a near-half marathon on a difficult […]
DU Dash 5K/10K
Experience the awe-inspiring beauty of Colorado's Palmer Lake area on the Santa Fe Trail for the in-person DU Dash. Runners will traverse the trail framed by the Rocky Mountains, connecting […]
Adidas Terrex Sunday Funday 5K
Vail Village 292 E Meadow Dr, Vail, CO, United StatesNEW COURSE FOR 2026! Kick off your Sunday the fun way with fresh air, fast feet, and a 5K full of good energy. The Sunday Funday 5K is just what you need to […]
Walk to Cure Arthritis
Together, let’s walk to a lifetime of Yes! Yes, to finding solutions, better treatments and a cure. Whether you have arthritis yourself or care about someone who does, sign up […]
Vitality Walk
Washington Park - Denver 701 S Franklin St, Denver, CO, United StatesYour participation in Vitality Walk helps Parkinson Association of the Rockies (PAR) push boundaries and invest in programs and services that are a lifeline to those with Parkinson’s, their Care […]
The Big Run 5K
Celebrate five decades of running with Fleet Feet at The Big Run presented by Brooks. This timed community 5K on Global Running Day is all about summer vibes, shared memories […]
M1LE Nation Challenge
One mile. One nation. Your best time. We’re bringing runners together for a nationwide mile race, and there are two ways to cross the finish line. Participate from your favorite […]
Adidas Terrex Pepi’s Face Off
Vail Village 292 E Meadow Dr, Vail, CO, United StatesGet ready for the thrill of a lifetime with the ultimate adrenaline rush: the Showstopper! This event is not for the faint of heart—it’s a wild test of brainpower, brawn, and […]
Canceled Gold Roots Trail Series #1
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 […]
Boulder Stroke & Stride II
Boulder Reservoir 5565 N 51st St, Boulder, CO, United StatesThe Boulder Stroke & Stride offers Boulder area athletes a fun 1-lap 750 Meter Swim, or 2-Lap 1500 Meter swim in Boulder Reservoir, followed by a 5k run on the […]
BRR Summer Track Series #1
Potts Field 4001 Discovery Drive, Boulder, CO, United StatesJoin the Boulder Road Runners as we host the premier track and field meet series in Colorado! Tradition runs deep with this legacy event. Now in its 4th decade, the […]
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 […]
All-Out Summer Breeze
From the heart of the West Metro area and the Stenger Soccer Complex, All-Out brings you our 11th annual Summer Breeze! Along with its Endless Series sidekick in January Polar […]
Climb 4 Change
Climb4Change is a unique racing event that offers various timed races on the 200-step Challenge Hill at Philip S. Miller Park. Participants ascend 178 feet at least once in any […]
Ironman 70.3
Boulder has been a household name in the world of triathlon for decades. This endurance community has built a reputation among triathletes for training hard, racing fast and enjoying every […]
Treat Trot
5k/10k/15k 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 medal! […]
Miles for Melanoma 5K
The Melanoma Research Foundation would like to welcome you to the 2022 Denver Miles for Melanoma 5K! This annual signature event will bring together local melanoma patients, survivors, care partners, […]
Stepping Stone 5K
Stepping Stone Support Center and Trailhead Community have come together to present this amazing event to benefit adults with developmental disabilities. Complete two laps of Johnson Reservoir at Clement Park […]
Fallen Officer Fund 5K/10K
The Annual Jeremy Bitner Memorial 5K/10K Walk and Run (3.1 miles/6.2 miles) will start and finish at Cornerstone Park in Englewood, CO. This course, which is certified, not only offers […]
CMRA John Meade 6K
We will start with a loop of John Meade Park before heading onto the Cherry Hills Trail for an out-and-back short cirtcuiting the initial loop. This race will be ~3.875 […]
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