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 area. Beyond the run, participants enjoy a festive atmosphere with food, beverages, an expo showcasing local race directors, running brands, and vendors, plus a raffle with prizes including race entries and running gear. Hosted in partnership with Runners Roost Boulder, attendees receive swag bags and discounts on store merchandise. The event fosters camaraderie and connection within the local running community. Visit the organization's website for the most recent information.

Race information

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