Kuruwa

The kuruwa serves as a defensive territory, provides space for additional castle facilities, and contains the living quarters for common soldiers, making it an important fixture of all Japanese castles.

Most castles built during the Middle Ages contain many kuruwa of small area, while those built during or after the early modern period often contain a lesser number of kuruwa of larger area.

The kuruwa regions were planned for after the basic layout of the castle grounds was decided.

The three basic kuruwa regions are the honmaru (本丸); the core of the castle, and the ninomaru (二の丸, lit.

Castles that use the naming -maru were built during the early modern period.