The castle, used as the base by Ieyasu Tokugawa and his successors, turned into Kyujo (place where Emperor lived) after the Meiji Restoration and was rebuilt as the current Imperial Palace.
その後徳川家康が本拠地を置き、徳川幕府が代々整備し、明治維新後は宮城となり現在の皇居となった。