The castle was designed as a ''[[hirayamajiro]]''. The ''honmaru'' was located on the summit of the hill with the ''ninomaru'', ''sannomaru'', and other fortifications laid out below. Katô’s structure was laid out to take full advantage of the natural formations of the landscape and would have been extremely difficult to attack. There is a ring of earthworks and ''[[ishigaki]]'' (stone walls) halfway down the hill and also at the bottom. The main ''tenshu'' has three exterior and four interior stories, including a basement. It uses traditional tile roofing and has striking black wooden walls. The layout of the rectangular ''tenshu'' complex somewhat resembles that of Himeji castle, albeit on a reduced scale. It has the main ''tenshu'' along with three other towers at the remaining corners. Typical of late Edo period castles, it uses a very straightforward and functional design with little enhancement or ornamentation. The ''tenshu ishigaki'' (stone walls of the main keep) are built using the ''[[uchikomihagi]]'' method with the outer ''ishigaki'' using the ''[[ransekizumi]]'' method. The outer stone walls are much higher than the norm for a castle of this size, being similar to the walls built at other castles by another famous Katô, [[Kato Kiyomasa|Katô Kiyomasa]] (no relation to Katô Yoshiaki). The castle now functions as a public park. | The castle was designed as a ''[[hirayamajiro]]''. The ''honmaru'' was located on the summit of the hill with the ''ninomaru'', ''sannomaru'', and other fortifications laid out below. Katô’s structure was laid out to take full advantage of the natural formations of the landscape and would have been extremely difficult to attack. There is a ring of earthworks and ''[[ishigaki]]'' (stone walls) halfway down the hill and also at the bottom. The main ''tenshu'' has three exterior and four interior stories, including a basement. It uses traditional tile roofing and has striking black wooden walls. The layout of the rectangular ''tenshu'' complex somewhat resembles that of Himeji castle, albeit on a reduced scale. It has the main ''tenshu'' along with three other towers at the remaining corners. Typical of late Edo period castles, it uses a very straightforward and functional design with little enhancement or ornamentation. The ''tenshu ishigaki'' (stone walls of the main keep) are built using the ''[[uchikomihagi]]'' method with the outer ''ishigaki'' using the ''[[ransekizumi]]'' method. The outer stone walls are much higher than the norm for a castle of this size, being similar to the walls built at other castles by another famous Katô, [[Kato Kiyomasa|Katô Kiyomasa]] (no relation to Katô Yoshiaki). The castle now functions as a public park. |