For modern grand sumo tournaments, a square-shaped platform made of clay having a side of 6.7 m is first built, and a circle having a diameter of 4.55 m (15 shaku) is defined at the center by placing 16 bales (Shobu-dawara) on the platform.
現代の大相撲では、一辺が6.7mの正方形に土を盛り、その中央に直径4.55m（15尺）の円が勝負俵（計16俵）で作られている。