A Volcano board is a 5 by 5 grid of squares. It got its name from Volcano, the first Icehouse game to use such a grid, although a physical board is not required for the game. Any 5x5 grid with squares at least 1 inch on a side will do, although many Icehouse gamers like to use a specially constructed board with raised borders between the squares that hold the pieces in place. This makes it easier to move the board without disturbing the pieces.