Ichinomiya Castle

Ichinomiya Castle is a mountain fortress located on the ridge of Ryuouzan at about 150 meters elevation, featuring stone walls and stairs across two distinct peaks. The site uses the natural terrain with its dual summits as a core part of its defensive design.

The fortress was built in 1338 by the Ogasawara clan to control the Awa domain, but their rule ended after conflicts between Emperor Godaigo and Ashikaga Takauji. The castle became a focal point during the period of political upheaval that followed.

The castle shows traditional Japanese fortification methods through its placement on high ground and use of natural defensive landscape features. The positioning on the ridge demonstrates how such fortifications relied on elevation to control territory and watch approaching forces.

The remaining stone walls and stairs are accessible to visitors, with clear markers guiding exploration throughout the site. Sturdy footwear is advisable since the stairs are steep and the terrain can be uneven in places.

During the 1585 siege by Toyotomi Hideyoshi, defenders surrendered without a fight after attacking forces cut off the castle water supply. The capture demonstrated how quickly a well-positioned fortress could fall when essential resources were interrupted.

GPS coordinates: 35.30169,136.80181

Latest update: December 12, 2025 08:00