Event details subject to change. Please confirm all information via event website.
Dirty Dozen Trail 10K
New Castle Trails’ 2026 Downvalley Dirty Dozen is a reimagining and celebration of trail running, mountain biking, music, and community. The weekend is full of fun including live music from regional bluegrass […]
Eltuck Valley 5K
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 […]
Eldorado Springs Run for the Cure
Founded in 1979, the Eldorado Run for the Cure is the longest operating charitable footrace in the State of Colorado. All proceeds from the annual four-mile run benefit the Colorado […]
BRR Summer Track Series #5
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 […]
Canceled High Five 100
In 2018 local ultra runners of Lake City came together to create a challenge meant to shake even the most elite runners to their core. What we came up with […]
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 […]
Jane Welzel Mountain Avenue Mile
Civic Center Park - Fort Collins Fort Collins, CO 80521, Fort Collins, CO, United StatesWhat is better than one day of running? TWO days of running! The Choice City Running Event on August 5th and 6th at Civic Center Park in Fort Collins has something for everyone. Kick off a weekend with the Jane Welzel Mountain Avenue Mile on Friday evening! Continue running strong the following day with the Human Race Half Marathon, 10K, and 5K. The party continues both days in the park with live music, vendors and a New Belgium beer garden!
CMRA/RMRR 5K
deKoevend Park 6315 S. University Blvd., Centennial, CO, United StatesJoin us for the August Trophy Series race and picnic at deKoevend Park in Centennial. This year our friends with the Colorado Masters will be joining us again for a […]
Ute 100
The Ute 100 is the highest and most scenic race in Utah, taking runners on a breathtaking tour of the La Sal Mountains, Utah's second highest mountain range. The 100 […]
Emerald Mountain Epic
The Emerald Mountain Epic presented by Hard Headed attracts some of the nation's best mountain bike and trail running racers, while still offering incredible opportunities for athletes of all skill […]
Reece’s Roundup 5K/10K
Join the Rubino Family at Philip S Miller Park in Castle Rock for the Annual Reece’s Roundup 5K/10K. This event supports Reece Rubino in his fight against Spinal Muscular Atrophy.
All-Out Runapalozza
As those summer mornings are just beginning to cool, join us for a celebration to end the season and our 11th Annual Runapalooza! From the award winning Apex Center, these […]
Georgetown to Idaho Springs Half Marathon
Part of the Colorado Mountain Half + Series, Georgetown to Idaho Springs Half Marathon is a Colorado Runner’s Must-Do. This iconic Half Marathon is one of the most pleasurable races in the […]
Summer Sizzler 5K
Join us for the annual Summer Sizzler! Whether you are looking to run, walk or just enjoy the race SWAG this race is a sure thing for a great time […]
Pat’s Pony Express Trail Run
Pat's Pony Express is a trail run at Rampart Reservoir. There are two distance options: 8 miles and 16 miles. Come out and enjoy the single track, running creeks, wildlife, […]
Run the Rockies Trail Half Marathon
The Run the Rockies Trail 5k, 10k, and half marathon will lead runners through the Frisco Peninsula trails with breathtaking views of Dillon Reservoir and the Ten Mile Range. This […]
Arapahoe Warrior 5K
Come out and support the Arapahoe Warrior Cross Country team at the 3rd annual Arapahoe Warrior 5K. $10.00 of every registration goes directly back to the Arapahoe Cross Country Booster […]
Escalante Days 5K
All proceeds support the Dolores Middle and High School Cross Country programs.
Dog Days of Summer 5K
Come join us on August 8, 2026 for a race around the entirety of beautiful Lake McIntosh! This 3.5 mile race is a half paved/half dirt course surrounded by wonderful […]
5K at the Fair
Please join La Plata County 4-H for the inaugural 5K at the Fair! The race will be on August 8 at 8:30 AM at the La Plata County Fairgrounds in […]
Strides For Change
Join us on August 8th, 2025 at Sloan’s Lake for Strides for Change – a 5K for Youth Mental Health, presented by Resolute Counseling Center. This community-centered event is more than […]
St Vrain for the Brain 5K
Run or walk this charity 5k in which all proceeds benefit brain cancer research! There will be trophies for the top finishers in men, women, and youth. Costumes are encouraged […]
HRCA Splash Mash Dash Kid’s Triathlon
Recreation Center at Northridge 8801 Broadway, Highlands Ranch, CO, United StatesThe Splash Mash Dash Kids Triathlon is the perfect for kiddos looking for a way to "TRI" the sport of triathlon or tune up their skills for a larger race. […]
Eat. Run. Adopt. 10K
Join us for Berthoud’s first-ever community-driven 10k! In partnership with Berthoud Pet Supply, this isn’t just a race—it’s a moving feast with a mission. A portion of race registration proceeds […]
Summer Sizzler 5K
Join us for the annual Summer Sizzler! Whether you are looking to run, walk or just enjoy the race SWAG this race is a sure thing for a great time […]
Rocky Mountain Tri-Fest
Rocky Mountain Tri-Fest is Colorado's newest Multisport event, catering to the whole family. With events for everyone from mom and dad looking to try their hand at a gravel triathlon, […]
Pancake Stampede 5K
Hudson Gardens and Event Center 6115 S Santa Fe Dr, Littleton, CO, United StatesWork up an appetite for a deluxe breakfast at The Pancake Stampede 5K on August 15th! The race is a part of Littleton's Western Welcome Week celebration and held before the annual pancake breakfast at Geneva Park. The 5K takes place at Hudson Gardens.
Bullfrog Summer Surge
The Bullfrog Summer Surge is a community first race morning built around movement, connection, and summer fun. Set at Addenbrooke Park, there's something for every pace: a timed 5K for […]
Canceled Gold Roots Trail Series #3
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 […]
San Juan Softie 100
The softest 100 miler in the San Juans This 100 mile ultra marathon starts and finishes just north of Durango, Colorado. The race will take you through some of the […]
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