Dirt Circus - Boulder

Table Mesa, United States • 9 Aug 2025

Dirt Circus - Boulder is a free community running event held in Boulder, Colorado, celebrating local trail running culture. Organized by UltraSignup, this one-day festival features a social group run with options of a casual 4.5-mile or 10K route through local trails. The event fosters camaraderie among runners, race directors, coaches, and local running businesses.

Participants enjoy post-run festivities including food, beverages, an expo with brand booths, and a raffle with prizes like race entries and running gear. Hosted in partnership with Runners Roost Boulder, attendees receive swag bags with running essentials. Dirt Circus highlights the vibrant local running community under a festive "big top" atmosphere. Visit the organization's website for the most recent information.

Race information

10 km
10k Run
4 mi
4.5 Mile Run
Visit the organization's website for the most recent information.
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