Boulder Marathon 2025 Calendar

Boulder Marathon 2025 Calendar. For each race, you’ll find the history of the half marathon and the course, the most recent year’s. Browse all colorado half marathon 2025 and 2025 by month and by city below.

The course takes you through the beautiful back roads of boulder, colorado at the foothills of the flatirons, before winding you to downtown boulder for an epic,. Named top 5 best half marathons in the us by active.