Ninomaru Palace is a National Treasure located in Nijo Castle. It is regarded as an important historical structure in Japanese architectural history and is a representative example of the shoin-zukuri residential style that was completed in the early Edo period. The interior is adorned with wall paintings by the Kano school, elaborate transom carvings, and decorative metal fittings, creating a lavish space befitting a shogun's residence. The palace consists of six buildings with the following rooms: The First, Second, and Third Rooms of the Waiting Area served as places where visitors awaited an audience, and the fierce tiger paintings and grand spaces conveyed the power of the Tokugawa family. The Reception Room, where matters and offerings for the shogun were handled, features wall paintings of pine trees symbolizing eternal prosperity. The Great Hall was the official meeting place for the shogun, daimyo, and courtiers, with wall paintings by Kano Tanyu. The Black Study, originally known as the "Small Hall" during the Edo period, was used for meetings with daimyo and high-ranking courtiers. The White Study served as the shogun's living room and bedroom, adorned with Chinese-inspired motifs. Additionally, there are other rooms such as the Fourth Room of the Great Hall and the Envoy's Room.The Ninomaru Palace also preserves approximately 3,600 wall paintings, and the wall paintings from the Kan'ei era, created by Kano Tanyu of the Kano school, were designated as Important Cultural Properties by the Japanese government in 1982.