Tenshu (main tower)

A Tenshu, or main tower, is the central, most prominent structure of a traditional Japanese castle. Typically built with multiple floors, it serves as a fortress, command post, and symbol of power. Architecturally distinctive, Tenshu often feature curved roofs, wooden construction, and defensive features like narrow windows. Historically, they provided strategic vantage points for monitoring the surrounding area and defending against attackers. Today, many Tenshu are preserved as cultural heritage sites, representing historical architecture and military innovation, and often serve as museums or tourist attractions illuminating Japan's feudal past.