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SEP 2026
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Boulderthon Boulder Marathon Presented by Puma
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Colorado Springs Marathon, Half, 5K, and Kids K
Colorado Springs, US
Boulderthon Boulder Marathon Presented by Puma
Sunday, September 27, 2026 · Boulder, United States
Distances
5K
10K
Half
Full
Start location
About this race
Boulder hosts this recurring road race, drawing "thousands of runners" to its streets. Recognized for offering "one of the best 5Ks in the country," the event also includes a marathon, half marathon, and 10K.
Runners can experience the "new HALF MARATHON course drop!" crafted by Boulder experts and noted for its speed. After finishing, participants are welcome at a post-race gathering, where the event offers a "classy" atmosphere.