Start Time: 7:00AM
3:00, 3:15, 3:30, 3:45, 4:00, 4:30, 5:00, 5:30
Pacing provided by BEAST Pacing
New Courses Announced! For our 6th Edition, we’re going back to our roots – now with even more beauty and speed.
Enjoy breathtaking views near the Reservoir, an epic Start & Finish in Downtown Boulder, and a 40–50% reduction in elevation gain.
This will be our most scenic and runnable course yet!
Start Time: 7:00AM
1:30, 1:45, 2:00, 2:15, 2:30, 2:40
Pacing provided by BEAST Pacing
Boulderthon was named among the Best Fall Marathons by Runner’s World, the Best Half Marathon in Colorado, and one of the Top 13 Most Beautiful Half Marathons in the World. Now in its sixth year, Boulderthon welcomes over 15,000 runners from all 50 states and 22 countries. Join us on Sunday, September 27, 2026, for the largest September running weekend in the U.S. in beautiful Boulder, Colorado.
Start Time: 8:10AM
Experience one of Colorado’s most scenic and exciting race weekends, powered by the natural recovery benefits of Cheribundi.
Cheribundi’s all-natural tart cherry juice is scientifically proven to reduce inflammation, improve sleep, and speed up recovery. Trusted by 475+ professional and collegiate sports teams, it’s the natural recovery choice for athletes and runners.
Start Time: 7:45AM
BCH is excited to partner with Boulderthon to present the 5K event, the Heart to Heart 5K. Research has shown that physical activity is one of the most important things you can do for your health, particularly cardiovascular health. Physical activities, such as running and walking, have been shown to reduce heart attacks, strengthen heart muscles and reduce blood pressure, amongst other benefits.
Start Time: 8:25AM
Join us on Sunday, September 27th, 2026 at 8:25AM for the fourth-annual Boulder Country Day School Kids Fun Run in Boulder, Colorado. The course starts at 19th and Pearl and ends with an incredible finish on the historic Pearl Street Mall! The Boulderthon is the perfect introduction to racing for your little ones! Parents can run for free with their child!?
Staged in the Happiest City in America (National Geographic), this is a race weekend that feels as good as it looks.
Now it’s time to experience it! Register today and join thousands of runners at the start line.
