Event details subject to change. Please confirm all information via event website.
High Line Canal Run
deKoevend Park 6315 S. University Blvd., Centennial, CO, United StatesThe 45th Annual High Line Canal 5K & 10K race takes place along the beautiful High Line Canal Trail. Registration includes post-race pancake breakfast.
Collegiate Peaks Trial Run
The Collegiate Peaks Trail Run takes place in Buena Vista, Colorado and offers two race distance options - 25 miles and 50 miles. The race was established in 1991 and provides a significant challenge of not only time but also physical and mental stamina. Beginning and ending near the Arkansas River in Buena Vista, the […]
runBlossom 5K
Event Information: For 20 years, the annual runBlossom race has helped usher in the summer season in Cañon City. As the snow melts and the leaves begin to adorn trees, runners of all ages come together to celebrate the Cañon City Music and Blossom Festival. The runBlossom 5K event showcases the Arkansas Riverwalk Trail, running […]
Niwot’s Challenge
Niwot’s Challenge is a very difficult, grass-roots, ultramarathon in Colorado’s Front Range. It is modeled after the arduous Barkley Marathons in Tennessee, and the historic More and More Difficult 50K in New Hampshire. Much of the information for this event is kept secret with an exception for those who are accepted for entry. This is […]
Duck Waddle 5K
Our Vision: Experiencing physical activity with a group encourages motivation, emotional wellbeing, accountability, fun and friendships. By providing athletic events we hope to inspire youth, families and individuals to enjoy building a community. We advocate for safe and connected multi-modal transportation that encourages mobility for all users. Our Purpose: The Estes Park Running Club organizes […]
Hope House 5K
Our 13 annual Hope House 5K & Fun Run will take place on Saturday, May 2, 2026 at the Promenade Terrace Park (South of the Westin Westminster)! It will be a fun-filled day full of fast runners, speed walkers, parents pushing strollers, smiley children, exciting finishes, an epic Diaper Dash, live music and more. Join us as […]
Furry Scurry
The Furry Scurry is an annual, pet-friendly, fun-filled festival and two-mile dog walk at Denver’s Washington Park to benefit the animals in our care. This year, people can gather in person on Saturday, May 2 OR walk from afar between now and May 11 (although we hope you’ll choose May 2 for your “virtual” stroll)! No matter where you scurry, […]
Longmont Half and 5K
Longmont's only Half Marathon - now offered in the cooler month of MAY! Join the Half Marathon or 5k distance! Walkers and Runners of all abilities welcome!
Moose Mudder
Please join us for the Annual Moose Mudder! This is a community event that will consist of an untimed 1k fun walk/run and a timed 5k followed by an optional muddy obstacle course. Get your best time, run for fun, walk with a group, form a stroller brigade, or line the streets to cheer everyone […]
Emerge 5K
The Emerge 5K is our biggest annual fundraiser, and the funds we raise ensure that we can continue to fulfill our organizational mission of breaking the social and financial barriers to mental health care for youth. Each year, Rise Against Suicide funds thousands of therapy sessions for youth under the age of 19 who are […]
Blue Ribbon 5K/10K
Grand Mesa Ultras
Come enjoy some of the best mountain running in Western Colorado! Our races are held on the Grand Mesa, the largest flat-topped mountain in the world where the average elevation is over 10,000 ft.
Frank Shorter Track Classic
Niwot High School 8989 Niwot Road, Niwot, CO, United StatesThe Frank Shorter Track Classic is a track meet honoring one of America's greatest distance athletes. Each year, we will celebrate Frank's career, his devotion to the sport of running and promotion of health and fitness, while also acknowledging a different Boulder Olympian. This year's meet will take place on May 21st at Nevin Platt Middle School in Boulder.
Best Buddies Friendship Walk
The Best Buddies Friendship Walk is the leading event in the country supporting inclusion for people with intellectual and developmental disabilities (IDD). Join 50,000 participants at 70+ Walks across the globe to support the Best Buddies programs in schools, workplaces, and communities. You’ll be making the world more welcoming to people with IDD — one […]
Quad Rock Trail Race
Welcome to the Quad Rock 50 and 25 mile trail races, an event put on by trail runners for trail runners. Taking place on the trails and hills west of Fort Collins in Lory State Park and Horsetooth Mountain Park, the Quad Rock 25/50 will take you on a tour of the Fort Collins skyline, […]
Valkyrie Women’s Trail Race
Valkyrie Trail Race was created as a women only trail/ultra event, featuring Colorado Spring’s, Cheyenne Mountain State Park. The race offers amazing views of the city and a diverse eco-system. We have several different distances available, so everyone in your running group can participate! 50K/Marathon/30K/Half Marathon/8 Mile/4 Mile
CMRA Tucker Lake 6.5
The race will start near the Colorado Tap House parking lot and head west along the Ralston Creek Trail toward Tucker Lake. Once reaching Tucker Lake runners will loop around the lake counterclockwise and then return on the trail back to the start.
Five Star 5K
Adams 12 Five Star Schools is invested in the Whole School, Whole Community, Whole Child (WSCC) approach to education and is committed to ensuring that all students are safe, supported, healthy, engaged, and challenged. This event is an opportunity for the Five Star Community to come together and celebrate this commitment to the overall well-being […]
Carbon Valley Half Marathon
Colorado at its Best – the Carbon Valley Half Marathon will showcase the beauty & diversity of Colorado’s best kept secret. Small town charm with Big City services, nestled between Denver & Fort Collins, Firestone & Frederick host these 13.1 mile & 5K adventures. Runners will tread upon Mining Town history via manicured trail systems, […]
Hometown Half Marathon
Join us for the annual Hometown Half Marathon & 5k/10k! A run local-themed event that is perfect for the whole family. The fun includes great swag (designer shirt, custom medal), chip-timing, live results and awards, pacers for half marathon free photos, a "biggest team" contest, a kids' dash, great post-race food, and plenty of fun! […]
Colorado Rockies Home Run 5K
Take part in the Colorado Rockies Home Run 5K Run/Walk (3.1 miles) that includes a scenic downtown course and lap around the warning track of Coors Field, there will also be a 1K fun run for kids and families with team mascots. Post-race festivities will include hot dogs, refreshments, music, and a beer garden. Your […]
Happy Smackah 5K
Join your fellow community members at our annual 5K Fun Run/Walk supporting local families facing medical hardship.
Mother’s Day Trail Run
A new Race Series for Colorado with 2 races over the Weekend for both WOMEN/Moms and their families!....Saturday, MAY 10th, 5k & Family 1 mile in Denver at GREAT LAWN PARK, then on THIS Sunday in LOUISVILLE- COMMUNITY PARK for the 5k, 10k and Family Mile Trail Races. Take your choice. LOUISVILLE- Expo opens at […]
Science Stride 5K
The Friends of the National Center Science Stride 5k brings together our community for a common cause: Inspiring the next generation of scientists! This event provides an excellent opportunity for everyone who believes in the importance of STEM education to come together and support Friends of the National Center. Runners and walkers of all abilities […]
Run for the Trees
We’re helping Parks and Rec celebrate Loveland's Arbor Day. Come enjoy food trucks, live music, and a 2 mile fun run to help raise money for the tree planting fund. Each participant will receive a custom bib, custom swag (TBD), and lots of FUN!
Women’s Distance Festival 5K
The Womens’ Distance Festival is no longer an event for “women only”. This event is now a “community” event, supporting the Girls on the Run® of the Rockies. Girls on the Run is a non-profit organization that uses the power of running to change the way girls ages 8-13 see themselves and their opportunities. Girls […]
Race for the Watershed 5K
Join us for a fun-filled day of running, walking, and most of all, supporting the Cherry Creek Watershed! Lace up your shoes and get ready to hit the trail with friends and family. Whether you're a seasoned runner or just looking for a leisurely stroll, this event is perfect for all ages and fitness levels. […]
Hometown Half Marathon
Join us for the annual Hometown Half Marathon & 5k/10k! A run local-themed event that is perfect for the whole family. The fun includes great swag (designer shirt, custom medal), chip-timing, live results and awards, pacers for half marathon free photos, a "biggest team" contest, a kids' dash, great post-race food, and plenty of fun! […]
Space Race 5K
✨Prepare for launch! ✨ The Wings Space Race 5K invites you to push past your limits and chase the stars into an experience that’s truly out of this world! Join us for an all-ages run and walk benefiting Wings Over the Rockies Air & Space Museum. This space-themed event invites participants of all fitness levels—whether […]
Colorado Women’s Classic
We are excited for the 2026 Colorado Women's Classic! While focused on women, all genders are WELCOME at this event!
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