The Nagoshi Festival is held to wish for good harvest and good health and is the largest festival held at Usa Shrine. The Nagoshi Festival is also called 'Battle Festival' because during the event, miniature shrines 'battle' with each other to become the leading shrine. Another name for the festival is Oharaie/Misogie.

The climax of the Nagoshi Festival is the battle of the three miniature shrines. On the first day, the three shrines head to the Tongu from the Uenomiya (or Okudari). Men dressed in white carry the miniature shrines and march through the shrine precincts, making a powerful sight.

When the shrines finally reach the Tongu, a time-honored ritual, the Suganukigyoji, takes place. It places three 'Heigushi' in the Mikegawa. On the second day, the miniature shrines do not play a holy role, so they are carried around for display. On the final day, the shrines are returned to the Uenomiya.