Birdy's Backyard Ultra is a "Last Person Standing" event at Lake Towerrinning in Western Australia.
In a last person standing event, competitors run a 6.706 km lap (4.167 mile) each hour, every hour and must finish their lap within the hour or they are out. The racxe continues until only one runner can complete the lap within the 1-hour time limit.
There is a maximum limit of 125 entrants for this event.
Last person standing, 6.7km per hour