In ancient times, sumo was one of the rituals to pray for a good harvest, a show of strength meant to entertain the Shinto deities. Tawara, or straw bales, were placed on the ground to mark out the wrestling area. The actions performed in the ring were refined into a series of rituals. In time, sumo itself became the main ritual of the festivities. In the Edo period, wrestlers organized groups to practice sumo professionally. Today, the sport is known as “Grand Sumo.” People come to watch the competition and experience the excitement.