Castle ruins of the Nanbu clan in Sannohe Town, Sannohe-gun, the site of the castle that the Sannohe Nanbu clan used as their base for approximately 300 years from the end of the Kamakura period to the end of the Warring States period. Sannohe Castle was built on a plateau flanked by the Mabuchi River and the Kengoshi River, functioning as the base for the expansion of Nanbu clan power. After Nanb…

Sannohe Castle is said to have been built by the Nanbu clan around the 14th century. In the Warring States period it served as the Nanbu clan's base, controlling parts of Iwate, Aomori, and Akita. After the Kunohe Masazane Rebellion of 1591, Nanbu Nobunao began building Morioka Castle and the role o…