Fort of medieval Japan

Medieval Japan was a time of intense domestic conflict, and forts and castles were built all over the country. The most typical military facility in medieval Japan was a castle with a keep tower, but there were also many simple forts without towers.
These simple forts are often built in terrain surrounded by cliffs or rivers, and are designed to take advantage of the natural topography to strengthen their defense.
Furthermore, the fort was designed to be surrounded by earthworks and moats as necessary to prevent enemy invasion and make it easier to defend.
The fort is not used in daily life, so it is not built to be suitable for daily life, but it does have the minimum facilities necessary for daily life, such as a well dug.

Just like castles, they were designed with both attack and defense in mind, so I think you'll find some very interesting things if you look at them from the perspective of both the attacker and the defender.