Event details subject to change. Please confirm all information via event website.
Central Park Kids Triathlon
Wellington Swim-Run Challenge
Swimmers may choose to swim with their shoes, paddles, a wetsuit, pull buoy, floaties, rubber duckies, inflatable flamingoes or any other nonmotorized swim aid in this event. Race Course Per Lap = 0.3 M Swim, 1.6 K Run Total: 3 Laps = 1 Mile Swim, 5K Run
PH in the Park
2026 marks 17 years of community, awareness, and fundraising to support people with pulmonary hypertension. The University of Colorado Denver, Children’s Hospital Colorado, and the Pulmonary Hypertension Association invite you to City Park in Denver for this annual 5K run/walk. Since our first event in 2008, this event has grown thanks to supporters like you. […]
Cooldown Denver
Eltuck Valley 12K
Lory State Park 708 Lodgepole Dr, Bellvue, CO, United StatesJoin us each Tuesday evening in August for a fun series of shorter midweek trail races. Our goal is to offer a fun, low-key series of races designed to give newer trail runners an opportunity to dip their toes into the trail racing waters, and to offer more experienced trail racers a chance to sharpen […]
Rock Hawk Trail Race
Held on the gorgeous, thrilling and rolling trails of Castle Rock’s Miller Park & Ridgeline Trail systems. While not overly technical, these trails will challenge and excite, as you soak up the amazing views. This is an excellent race for both first-time and veteran trail runners, and provides a nice test for those who are […]
Boulder Sunset Triathlon
Summer may be coming to an end, but our tri season is still heating up! Join us at the Boulder Reservoir for the 13th Annual Boulder Sunset Triathlon, a local favorite. For the 5th year in a row we are the proud host of the Mountain Collegiate Conference race and the USAT Duathlon Race Series. […]
YMCA of Pueblo Indoor Triathlon
Take on the challenge of the YMCA of Pueblo Indoor Triathlon, a fun, beginner-friendly event that combines swimming, cycling, and running in a supportive environment! Participants will complete a 10-minute swim, 20-minute bike ride, and 10-minute treadmill run, with transition time between each segment. Unlike a traditional triathlon, athletes compete based on the total distance […]
Waneka Classic Community 5K
A free, timed 5K, open to the public, held prior to the Centaurus Cross Country Invitational. Proceeds from the World Famous Concessions Stand and T-shirt sales benefit the Centaurus Cross Country Team. Stick around and watch Colorado's best student-athletes run the same course. A note about parking: Parking is available throughout the Waneka Lake residential […]
RexRun 5K for PAWSitivity
The RexRun 5K is a 5K run/walk to spread mental health awareness and #PAWSitivity in schools with the help of more Therapy K-9's like Arapahoe County Sheriff's Office K-9 Rex. This year's event is at Dove Valley Park in Centennial on August 6th.
Boulder Sunset 5K/10K
The Boulder Sunset 10K & 5K Run is part of BBSC’s biggest endurance event of the summer. Spend your weekend racing with BBSC at the incredible and scenic Boulder Reservoir. Register, and start training for the end-of-the-summer endurance festival with BBSC.
Thirsty 13 Half Marahton
It's a race. It's a Brewfest. It's the Thirsty 13 Half Marathon! Are you thirsty for gorgeous scenery? You won't find a course more beautiful than this one. With the majestic La Plata mountains in the background, you'll cruise through the lush pastures of Wildcat Canyon and past the pristine waters of Lake Nighthorse. This […]
Rocky Mountain 5K
In partnership with the YMCA Pikes Peak Region, we want to bring you the annual Rocky Mountain Run, the Rocky Mountain State Games official 5k! Athletes will be looped around Memorial Park starting at the IAFF Fallen Firefighters Memorial then head through the side streets of Memorial Park, around Prospect Lake, and finish back at […]
Nebraska State Fair Marathon
The Nebraska State Fair Marathon will include several different races for the entire family. The races include a Marathon, Half-Marathon, Relay Marathon, 5K, 1-Mile Kid Run, Push Rim Wheelchair, and Handcycle. All races will start and finish on the Nebraska State Fairgrounds.
Historic Main Street 5K
Join us for this family-friendly event! The 5K run/walk will begin and end on Elizabeth’s historic Main Street, featuring a new and exciting course that crosses the reconstructed trail bridge and heads north into Evans Park, with a mix of pavement and dirt for varied terrain. The Family Color Run will take place in Running […]
Run Like The Wind 5K
Come race in the mountain town of Allenspark Colorado. Run the scenic 5K that circles through downtown and along dirt roads amid pine forest, boasting awe inspiring views of Mount Meeker and the Continental Divide. Enter your dog to run with you for an extra $5 and stick around for the post-race whimsical dog show. […]
Summit UP Run
We're bringing back our Summit UP Run presented by Mammut during Union Peak Festival weekend with spectacular views to jump-start your Saturday morning before relaxing and listening to music! Choose from a 5k or 5k Challenge route—both start & end at Aerie, located at the top of American Eagle lift. Celebrate your athletic pursuit at the Aerie […]
Run for Hope 5K
This year will mark our 3rd annual Run For Hope when we remember, honor, and celebrate those who lost their lives to addiction. This year's event is hosted by our Finding Hope and Hope After Loss Support Groups. We currently have over 800 members across the United States who attend these free support groups to […]
Ouray 50 Mile
A 50 That's More Difficult Than Your Last 100 How do you build a 50 miler that hits harder than most 100 milers? Easy. Start with a stout mountain hundred miler. Anything with ~24k feet of climbing should do. Find 50 miles of flat and discard it. Add copious amounts of highly-technical, unforgiving, why-would-they-even-think-this-is-a-good-idea trails. […]
Glow and Roll 5K
Glow & Roll is an inclusive, dusk-time 5K Walk/Run/Roll (with a 1.6-mile option). A glow-filled, twilight experience with lights, music and day-glow swag that transforms the event into a celebration under the evening sky. Movement in all forms is welcome whether you walk, run, use a wheelchair, or dance your way through the course. Creative […]
RMRR Fall Marathon Training Series #1
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, […]
Louisville Fall Splash & Dash
Get ready for a fun, energetic racing experience! The event features an indoor swim in the Louisville Rec Center pool, followed by a run on the outdoor trail. This series is open to kids ages 5–14. Age Groups & Distances 5–8 yrs: 50-yard swim / 0.65-mile run 9–11 yrs: 100-yard swim / 1.3-mile run 12–14 […]
Raising the Barr Ultra
Introducing the Raising the Barr Ultra Race. Try to finish as many 10 mile loops around the lake in the first 4 or 10 hours and then switch to 1 mile loops for the last few hours of your race. Registration includes bib, t-shirt, and post-race meal.
Roost Rebellion Relays
Welcome to the Roost Rebellion Relays! Assemble your fastest 4 x 1 mile relay team to race in Washington Park. Each team needs to be co-ed with at least 2 women. Here's the catch! Each team must select at least one participant to race in Mizuno's super shoe - the Wave Rebellion Pro. This ultra […]
Front Range Ultra Dayze
Welcome to Front Range Ultra Dayze! 100 hours of ultra-running madness! Our goal is to bring people from all over the U.S. together for a festival of ultra-running in Loveland, CO. All distances are ultra-distances, because there’s no community like the ultra-running community! Runners are allowed to camp at the park from start to finish […]
Grand Traverse Mountain Run
The Grand Traverse Mountain Run is a point-to-point ultra marathon from Crested Butte to Aspen, Colorado. The course follows the route of the Grand Traverse Backcountry Ski race. In total, runners travel 40 miles across the Elk Mountains with over 6,000′ of elevation gain.
The Beaver Run
The Beaver Run is a high-altitude mountain running event held Labor Day Weekend in beautiful Breckenridge, Colorado. Participants can choose from 5K and 10K distances along Breckenridge's scenic paved recreation path system while enjoying mountain views, fresh alpine air, and a festive holiday weekend atmosphere at approximately 9,600 feet above sea level. Hosted by BA […]
Recovery Run of the Rockies 5K
Join us for the 4th Annual Recovery Run of the Rockies 5K on Saturday, September 5, 2026, at Fossil Creek Park in Fort Collins, Colorado! This professionally timed 5K brings runners, walkers, families, and community members together for an energizing morning celebrating recovery, health, and hope. Whether you are racing for a personal best, enjoying […]
Golden Harvest Half Marathon
5k/10k/Half Marathon 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! The kid's dash is a fun, untimed dash for our kiddos ages 10 and under. Registration includes a mini bib, youth-sized shirt, and a […]
Break Your Neck 5K
Come join us to celebrate the access/disability community and raise money for spinal cord injury rehabilitation and awareness. My name is Kenny White III. On November 15 of last year, I suffered a Burst fracture to my C6 vertebrae. After emergency surgery I woke up a quadriplegic. After months of rehabilitation and hard work, by […]
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