Boulderthon Half Marathon 2024 Dates

Boulderthon Half Marathon 2024 Dates. Stunning course tucked away at the foothills of the rockies. Boulderthon is colorado's largest fall race series with 5k, 10k, half marathon and marathon options.

See course maps, elevation profiles, reviews, pricing, and how to sign up for each race. Find half marathons in colorado by date and city for 2024 and 2025.