First Floor
Although the main keep was built primarily as a fortress, the first floor has a mix of living quarters and defensive features. There are four rooms in the center, including a room reserved for the exclusive use of the lord of the castle when he was in residence there. This room has a hidden compartment for concealing samurai who would be at the ready to assist their lord if needed. Surrounding these rooms is a wide corridor known as a mushabashiri (literally “warrior run”) which is wide enough for warriors to assemble and move around the castle should it come under attack. Note the well-worn yet sturdy wooden floors.
Another defensive feature of the first floor is the “stone-drop” (ishiotoshi) chambers at the northwest and northeast corners. From inside the castle, defenders could launch surprise attacks against intruders trying to scale the castle wall by dropping stones or boiling water on them.
The windows are fitted with wooden slats set at an angle that allowed defenders to shoot arrows or bullets while also being shielded from return fire.