Zombie Backyard Ultra has runners complete a 4.167-mile loop at Oak Mountain State Park each hour, with a bell signaling who continues in the race. This is a summer backyard ultra, meaning the event concludes when only one runner remains. The start-finish area doubles as a camp, where athletes rest, refuel, and prepare for the next hourly circuit.
Runners must be in the corral and back on course when the bell rings, or they are disqualified. The field is limited to 100 participants, and many entrants are familiar with the backyard format. Local runners, returning competitors, and visitors from places like Kentucky attend. Crews and volunteers set up tents near the finish and offer support throughout the day and night, as participants aim for the "last zombie standing" title. The race, though relatively new, already has repeat runners, and its event record is 25 loops, covering over 104 miles.