The Underground Circus 100

The Underground Circus 100

The Underground Circus 100 is a trail and road ultrarunning event held on the Silver Comet Trail in Smyrna, GA. The course is primarily flat with asphalt and grassy sections and about 125 ft of elevation change. The trail remains open to the public while aid stations are staffed during the event.

Participants may choose from multiple timed formats and distances:

• 100 Miles
• 50 Miles
• 24 HR
• 24 HR RELAY
• 12 hours
• 6 hours

The course is an out-and-back format with a straight 10 mile outbound section, one street crossing, and a return loop. Laps are recorded with a timing mat and runners are signed in each loop; personal GPS watches may also be used but laps must be recorded by race timing. Aid stations at the start are fully stocked with drinks, snacks, and hot foods. One indoor bathroom is available 24 hours and another bathroom near mile 5 has limited hours. Several nearby businesses have indoor restrooms and runners are asked to respect those facilities.

The event enforces sanitation and no-refund policies, allows distance transfers on payment of any difference, and collects donations and proceeds to benefit people experiencing homelessness. Volunteers receive swag and may earn free entry to next year after an eight hour shift. Night running requires a headlamp or reflective gear for safety. Littering is prohibited. Visit the organization's website for the most recent information.