Run Boulderthon: The Boulder Marathon
SEP
27
2026
Marathon
Half Marathon
10 kilometers
5 kilometers
Always double-check with the organizer's website! This page may contain affiliate links.
About the race
The Run Boulderthon: The Boulder Marathon will take place in Boulder on Sunday 27 September 2026. You can run between 5 and 42 kilometers. Visit the organization's website for the most recent information.
Marathon
Marathon
Half Marathon
Half Marathon
10 km
10k
5 km
Heart to Heart 5k
Boulder Country Day School Kids Run