Big's Backyard Ultra

Big's Backyard Ultra is the original backyard ultra, invented by Gary "Lazarus Lake" Cantrell of Bell Buckle, Tennessee. Participants run a 4.167-mile loop every hour, and are eliminated if they fail to complete a loop in an hour. The path of the loop is on trails during the day and along a road after dark. The distance of each loop is equal to 100 divided by 24, so that a competitor runs 100 miles for a full day of competition. There is no predefined finish. The winner is the competitor who completes a loop that no other competitors complete. If no competitor outlasts every other competitor, there is no winner.