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, allowing runners to connect with the local running community. The event includes an expo with local race directors, running brands, coaches, and vendors, plus food, beverages, and a raffle with prizes such as race entries and running gear. Participants receive a swag bag with products from sponsors like Skratch Labs and Sidas. The event is hosted in partnership with Runners Roost Boulder, offering attendees discounts on gear. 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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