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, the event features a social group run with options of a casual 4.5-mile or 10K route through the local trails. Beyond running, the festival offers food, beverages, a raffle with prizes, and an expo showcasing local race directors, running clubs, brands, and businesses. Participants receive swag bags with running gear and nutrition products. The event fosters camaraderie among runners and industry partners, highlighting 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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