*japan-guide.com Honmaru Goten (本丸御殿) , meaning "the palace in the inner-most circle of defense", is the only surviving building of the former Kawagoe Castle. It used to serve as the lord's residence and offices . Kawagoe Castle was originally built in 1457. When Tokugawa Ieyasu took over its rule, he installed an important loyal subject as its lord, due to Kawagoe's importance as a trade city and a strategic point of defense north of the capital. Throughout the Edo Period, 21 lords, all closely allied with the Tokugawa Shogunate, resided at Kawagoe Castle . Today's structure was added to the castle in 1848, shortly before the end of the feudal age. Recently renovated and reopened to the public in 2011, it has spacious tatami rooms, a garden, and pictures of cultural heritage which are put on display. Visitors are also able to sit with three models of a feudal lord and his vassals, and imagine what it must have been like to hold a discussion in that room.