Established in 1370, Tozenji Temple is the oldest temple in Kamimashiki County. It was later revived and turned into the family temple of Mifune Castle lord Kai Soun. Housed inside are several objects, such as a wooden Shaka Triad statue designated as a Kumamoto Prefectural Important Cultural Property and three historical assets belonging to Zen master Toshun Juso: a portrait, book, and stupa. Other items kept here include Soun’s favorite tea kettle and war fan, known as a gunbai, as well as a portrait of him.
The graves of Kai Soun and his wife are situated in a hilly area not far away from the temple.