Ninohe City is located at the northern tip of Iwate Prefecture's inland area. The current city is the second in its series, formed in 2006 by the merger of the former Ninohe City and Joboji Town in Ninohe County. The former Ninohe City is bordered by the Mabechi River in the center and Mount Orizume to the east, while the former Joboji Town is bordered by the Appi River in the center and Mount Inaniwa to the west. The name Ninohe comes from the "Four Mon and Nine Mon" system established in the old Nukabe County, which divided Nukabe County into four gates and nine towns. "To" means "ranch," and the names Ichinohe through Kunohe, excluding Shinohe, remain as place names to this day. Major tourist attractions include the Kunohe Castle Ruins, a national historic site, Kindaichi Onsen, and Inaniwa Plateau.