Sasayama Castle Ooshoin

This flat mountain castle was built in 1609 as part of the "Tenka Fuchin" project, in which various feudal lords in the western part of Japan were mobilized to build the castle under the master builder, Takatora Todo's layout. The castle was built very solidly, partly as a preparation against the western provinces. However, it is said that the castle was so well defended that the Shogunate was wary of it and did not build a castle tower.

Instead, the Ooshoin was built in Ninomaru, and became as magnificent as the largest building inside the Ninomaru Palace of Nijo Castle, the Tou-Samurai. Although it remained intact after the Meiji Restoration, it was destroyed by fire in 1944. However, it was rebuilt in 2000 with donations from citizens, and is now open to the public as a historical museum.

The buildings of the Ninomaru Goten, except for the Ooshoin, could not be restored due to a lack of data. Therefore, the layout of the buildings is marked on the ruins of the palace, so that visitors can imagine what the palace used to be like in the past.

The ruins of the castle are still a popular place for citizens to relax, and the ruins of San-no-maru are the site of the Dekansho Festival. Aoyama Shrine, dedicated to the distant ancestors of the Aoyama family who were feudal lords, is also located at the site of the main castle.