The playing area is usually flat area such as basketball courts, tennis courts or driveways, once a player has set a foot down on the ground and is eliminated they may use their bike as a border, all the eliminated players will create the circular border making the area smaller and smaller as the final participants battle to the end.
The playing area is typically a flat surface used in games where elimination occurs, with players using bikes as boundaries to shrink the area as the game progresses.