Event details subject to change. Please confirm all information via event website.
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 5K, 10K & Half Marathon courses will run west along the 2020 Best of the Best Ralston Creek Trail through Arvada's open spaces and stunning golf […]
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 western US. The point-to-point course is a scenic and gently rolling downhill mountain course that winds down the Clear Creek Valley -- starting at an […]
Human Race Half Marathon
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 in Civic Center Park Fort Collins has something for everyone. Kick off a run-filled weekend with the Jane Welzel Mountain Avenue Mile on Friday evening with 1-mile races for everyone including kids, middle & high school students, families, […]
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 and an incredible experience! This is a fun, family event for all ages with all distances! Great Swag - designer shirt & custom medal Chip-timing […]
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, and Colorado's autumn glory. This race is small by design and always will be. The US Forest Service limits the number of participants so the […]
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 is a great course for a first time half-marathoner or runners looking for a fun course that offers single track and dirt road trails. Racers […]
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 team.
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 mountain views, vast farmlands, and beautiful aquatic wildlife! Gather at Dawson Neighborhood park near the pirate ship playground where you will find an assortment of […]
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 Durango, 2500 Main Ave. Check in starts at 8 AM. We will be meeting on the lawn, next to the Extension Building. Runners and walkers […]
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 a race — it’s a movement to support and uplift the mental health of our youth. Hosted by Resolute Counseling Center, whose mission is to […]
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 — the best costume wins a prize!
Sarcoma Strong 5K
Hi all! Please join us at Sloan's Lake Park in Denver on 8/8 for a 5K to raise awareness for cancer! Specifically, sarcomas, a group of cancers that affect tissues such as bone and muscle. We hope to raise awareness for these often deadly, debilitating, and often overlooked cancers; for survivors, families, and the research/medical […]
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 will go to Scroungy Dogs and Pretty Pups Rescue This community race and expo is designed to support Scroungy Dogs and Pretty Pups Rescue, a […]
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 and an incredible experience! This is a fun, family event for all ages with all distances!
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, to children looking to do their first triathlon. The Sprint and Super Sprint gravel Tris are beginner friendly with the bike course on the gravel […]
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 PR chasers, a relaxed Hot Lap for walkers and joggers, and a Kid's only version of the half mile Hot Lap for tadpoles ready for […]
Berkeley Circuit
Event Description Berkeley Circuit Race Schedule: 8:30- Free and Fun Kids Quarter Mile (no registration necessary, just show up to race!) 8:45- Community One Mile Run (all paces welcome- walkers, strollers, dogs!) 9:15- Competitive Waves Begin (10 person waves from slowest to fastest seed times) *All registered participants will receive a performance race tank with original […]
Summit Trail Running Series V
Carter Park 500 South High Street, Breckenridge, CO, United StatesExplore the trails of Breckenridge this summer with the 23rd annual Summit Trail Running Series with each race followed by a post-race party! The Series consists of 5 trail races in and around Summit County, May-July. Each race features a short and long course, and all races are open to runners of all abilities ages […]
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 most stunning and rugged terrain with breathtaking views of the Colorado Trail, Engineer Mountain, Wilson group of 14ers, Lizard Head, and many other incredible peaks […]
Weld County Commissioner’s Cup
This is a private event for Weld County employees and their families. The race is not open to the general public. Sorry!
Roxborough Ultras
Roxborough Ultras is a late-summer trail ultramarathon in Roxborough State Park, Colorado, offering a 50K and 50M on fully marked, all-trail courses. Both distances feature sustained climbing, technical sections, exposed terrain, and long stretches with little flat relief. The 50K includes over 5,000 feet of elevation gain. The 50M includes over 9,000 feet of elevation […]
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.Now in its 12th year, Westminster Trail Race continues to be one of the Front Range’s most approachable and scenic trail events. The courses wind along […]
Mt Sneffels Half Marathon
The Mt. Sneffels Half-Marathon and Kids Fun Run began 25 years ago. In 2021, the 10 K was added. The Race is the foundation’s major fundraising event of the year. It is supported by sponsorships from businesses and individuals, over 400 race participants nationwide, 100 plus volunteers, and a dedicated race committee offering their time and […]
Boulder Rez Marathon
The Boulder Rez Marathon is quickly becoming a Boulder classic! This isn’t just another run around the lake. September temperatures will create the perfect race atmosphere. BBSC will offer a Marathon, ¾ Marathon, Half Marathon, 10K and relay, guaranteeing the perfect distance for you! This popular course will take runners around the Boulder Reservoir on […]
Cheyenne Mountain Run
The Cheyenne Mountain Run in Colorado Springs will take place on October 8, 2022 and will feature 3 trail races: a 25K to the top of Cheyenne Mountain for the more advanced trail runner, a 10K for the experienced runners and a 5K trail run for all to enjoy.
Med Bow Rail Marathon
The Friends of the Medicine Bow Rail Trail will host the second annual Med Bow Rail Marathon & Half Marathon on August 13th, 2022 at Lake Owen in the Medicine Bow National Forest near Laramie, Wyoming.
Dash for Democracy 5K
Dash for Democracy is the Denver Democrats' 5th Annual 5K Run / 2K Walk, taking place at City Park and bringing together community members for a morning of fitness, civic engagement, and fun. This election-year event is an opportunity to connect with neighbors, learn about candidates and issues on the ballot, and celebrate the importance […]
Frontier Academy Community 5K
The Frontier Academy Community 5K is meant to serve the community of Greeley and the surrounding area. Through this race we hope to fulfill the vision and mission of our school - 'Building Leaders'.
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