This was the blueprint for the main keep of Koga Castle during the Edo Period.
Taken inside the Koga City History Museum-where this is a giant hanging screen.
Koga City, in Ibaraki Prefecture, Japan, has a history that dates back to ancient Jomon times and was even mentioned in the Man’yōshu anthology of poems that was compiled in the AD 800s. During the Muromachi period, Koga became the base for the Kantō branch of Ashikaga under the leadership of Shigeuji, who led a rebellion against the Ashikaga shogunate.
During the Edo period (1603-1868), the fief of Koga was ruled by many hereditary daimyo whose families had pledged loyalty to Tokugawa Ieyasu prior to the battle of Sekigahara in 1600. The families that ruled Koga included the Ogasawara, various branches of the Matsudaira, Okudaira, Nagai, Honda and Doi. Perhaps Doi Toshikatsu, who became tairō (chief elder of the council of elders - rōjū) during the reign of Shogun Tokugawa Iemitsu, was the most famous ruler of Koga.
Another famous ruler of Koga was Doi Toshitsura (1789-1848), who is sometimes called the “The Snow Lord”. Apart from being a key advisor to the Tokugawa shogunate, he was the first person in Japan to seriously study the designs of snowflakes. He illustrated his findings in a book Sekka Zusetsu (Pictorial Illustrations of Snowflakes) and some of the patterns became popular for clothing and decorative purposes.
Today, there is nothing left of the Edo period Koga castle, but numerous old temples, shrines, samurai and farmer homes remain. Unfortunately, many of these buildings suffered damage during the magnitude 9.0 earthquake that struck northeastern Japan on March 11, 2011 and repairs were ongoing when I visited.