A fort located at a strategic location on a sea coast, riverbank, or island. It was furnished with large guns. Daiba were…

Also written 大陰虎口. A simple, early form of castle entrance *koguchi …

Lit. large *tenshu 天守. The principal tower. The largest tenshu in a…

A wall projecting 15-30 cm outward from the flat top, *inubashiri 犬走り, of a…

A compound that juts out or is slightly separated from the main components of a castle complex, which include: the main…

1　Outer citadel. Also tsukejiro 付け城, hajiro 端城, edajiro 枝城. A type of branch…

A loophole, *sama 狭間, that projects out from the frame of a window opening in…

1　Lit. earthen bridge. An earthen bridge, which is made by leaving an unexcavated section of moat in front…

Also dorui 土塁. An earthen embankment, earthwork, or rampart. A defensive embankment surrounding a castle or a…

The foundation bed, shiki 敷, of an earthen embankment, *doi 土居. It has…

Lit. independent donjon or keep. Also called dokuritsushiki tenshu 独立式天守, dokuritsu tenshukaku 独立天守閣. A…

1　The flat top of an embankment, *doi 土居, also called *…

A widely used moat with sides that slope like an earthen embankment. The name is derived from the moat having a bottom with…

A guard tower set atop the corners of a castle's stone wall and other strategic positions overlooking the surrounding area.…

Also written 屋形城.

1　A structure that combines the daily living quarters of a mansion with the…

A mountain castle entrance. The entrance *koguchi 虎口 of a mountain…

Lit. "mountain castle." A castle built on a mountain to take advantage of the mountain's topography. One of the three main…

Lit. "mountain eye pounding and inserting piling." A dry construction method used to pile stones for a stone wall *…

A loophole for thrusting pikes and spears. Typically, they are installed in narrow locations beside main castle entrances…

A small castle or fortification built like a a country house or mansion yashiki 屋敷. In the middle ages, it usually…

An arrow loophole in a castle wall. Also sengan 箭眼. Characterized by a vertical opening about 45 cm high (1 …

Positive castle entrance or yang entrance. A generic term for various types of castle entrance *…

Also written 用害.

1　A place of strategic importance, having steep terrain that is easy to defend. In…

A lateral dry moat excavated crosswise in front of a mountain castle *yamajiro…

A side loophole of the *yarisama 鑓狭間 type for pike and spears. Typically…

Lit. "side arrow."

1　Attacking from the side. Also sokusha 側射, sokubō 側防. An…

Also written 横矢斜 and 横矢歪. Lit. "distorted rampart." A diagonal projection from a castle rampart. Used by defending troops to…

Also termed demasugata 出桝形. A defensive box-shaped courtyard *masugata…

Also written 横矢隅落. A diagonally cut-away corner of a castle tower, used to launch side attacks *…

A post set against a castle's sloping stone wall, at the same angle of incline, under the watch tower gate *…

A cul-de-sac compound. A long and narrow castle compound with only one gateway entrance which turns into a blind alley.…