The Underground Circus 100

Smyrna, United States • 4 Jul 2026

The Underground Circus 100 : Smyrna, GA

The event takes place on the Silver Comet Trail and offers timed and fixed-distance options on a mostly flat, fast route with mixed surface options: asphalt, gravel and grass. The course follows a straight out-and-back layout of roughly 15 miles each way with about 125 feet of elevation each way. The trail is open to the public and includes wooded sections, trees and several scenic views such as 18th century homes and historic battle sites.

Distances offered include:

  • 100 Miles
  • 50 Miles
  • 24 Hour
  • 24 Hour Relay
  • 12 Hours
  • 6 Hours

Support includes three staffed aid stations located about every five miles, a timing mat and volunteers to verify laps. Two indoor restrooms are available on the trail; one remains open throughout the event and the other (past mile 5) closes at sunset. Night runners must use a headlamp or reflective gear for safety. Parking is available at the start area and nearby shop lots; there are no electrical hookups for campers or RVs.

Awards include a customized brass buckle for the 100 mile finisher and finisher awards for shorter distances. The event is a fundraiser for the homeless and accepts donations of basic toiletry and clothing items. Transfers between distances are allowed with payment of any difference; refunds are not offered. Visit the organization's website for the most recent information.

Race information

100 mi
100 Miles
50 mi
50 Miles
6hrs
24hr Relay
24hr
12hrs
Visit the organization's website for the most recent information.
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