This is the clan fortress of one of the three great ninja, Hattori Hanzo, and there are commemorative markers at the birthplaces of Hattori Hanzo and Todo Uneme. Todo Uneme was from the Hoda family of the Hattori clan, and served as chief retainer of the Yoyo Ueno Castle. Nearby is the Hanagaki Jinja Shrine, wherein are enshrined the guardian deities of the Hattori clan.