Event details subject to change. Please confirm all information via event website.
Boulder Stroke & Stride I
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 […]
First Fridays 5K
Festival Park 199 Perry St., Castle Rock, CO, United StatesFriday nights in the summer are made for spending time close to home, enjoying the beautiful weather, and unwinding from the long week. Why go anywhere else but Downtown Castle […]
Summits Trail Runs
The Summits Trail Runs occur at Granby Ranch Resort in Colorado’s beautiful Rocky Mountains. These challenging trail races offer a variety of distances ranging from shorter runs to ultra distances, […]
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 […]
Basalt Half Marathon
The Basalt Half Marathon is a fast gradual downhill race on a scenic 2 lane road along the Frying pan river. This race is a fundraiser for the Basalt High […]
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 […]
Steamworks Half Marathon
The Steamworks Half Marathon will take place in the San Juan Mountains . This high-elevation, 13.1 mile race will take place at 6,500 feet above sea level. The course is […]
J-Town Jog 5K
Get ready to rumble at the J-Town Jog 5K and Mile, an annual family-friendly event to kick off Johnstown Barbeque Day! Runners and walkers of all ages and abilities will enjoy […]
Step Up For Women And Recovery 5K
This event brings together the community and supports scholarships for women who seek treatment for drug and alcohol addiction. People entering a program often have the commitment to complete treatment […]
Haul Ass Ultra Running Festival
Come out and enjoy a unique running experience at the beautiful Luvin Arms Animal Sanctuary with live music, food, and fun! Flat & fast off-road cross country style course with […]
Berthoud Day 5K
The Berthoud Day 5K is a fun, family-friendly race that kicks off the Berthoud Day Parade with energy, connection, and hometown pride. Open to runners, walkers, families, strollers, and even […]
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 […]
5K In My Shoes
The 5K In My Shoes event will return to Envision (1050 37th Street Evans, CO 80620). Check-in/registration starts at 7:30 AM and the race begins at 8:30 AM. The start […]
Centennial Airport Runway 5K
Planning for the 2026 Centennial Airport Runway 5K is officially underway – and while we’re still finalizing many of the details, one thing is certain: race day will be packed […]
Valley Bottom Rio Trio
Alamosa Parks and Recreation and Adams State Adventure Programs are partnering to bring the San Luis Valley the first annual “Valley Bottom Rio Trio”; an adventure-style triathlon race within the City of Alamosa on June 12th. This fully chip-timed race will feature an 8-mile trail bike ride, a 3-mile paddle on the Rio Grande, and a 5k run.
Aiden’s Adventure 5K
Let's help Aiden give back to his community and honor him in such a loving way. Aiden's Adventure 5k is designed to remember Aiden, a sweet, caring, "never met a […]
Creede Donkey Dash
IMPORTANT: Please do not register for this race until you have been matched with a donkey teammate! Race registration is separate from a donkey rental. Donkeys first arrived on US […]
Mickelson Fast 5K
Part of the Deadwood Mickelson Trail Marathon event.
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 […]
Flamingo Day 5K
Join us for a fun and festive day at Denver's Sloan's Lake Park.
Deadwood Mickelson Trail Marathon
26.2 Miles of Black Hills, South Dakota Beauty!
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 […]
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 […]
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 […]
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 […]
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 […]
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