Kaneda-jo Castle (an ancient mountain castle in Tsushima Province during Asuka period) (金田城)
Kaneda-jo Castle (also known as Kanetanoki Castle) is an ancient mountain castle (Korean-style mountain castle) built in Tsushima Province during the Asuka Period. It is located in Kurose Joyama, Mitsushima Town, Tsushima City, Nagasaki Prefecture. A national special historic site.
Kaneda-jo Castle is situated on Mt. Jo (also known as Joyama) 275 meters above sea level which stands on the south shore of Aso-wan Bay in the central Tsushima. There are stone mounds on the top of Mt. Jo and stonewalls were built to encircle that hill. The southeastern foothill forms a relatively slow slope and there are castle walls along the three dales leading to the sea (that are referred to as 'First Castle Door,' 'Second Castle Door' and 'Third Castle Door,' respectively) that still remain in existence today. It is considered that a lock and castle gate also existed. Additionally, a number of remains of buildings were discovered around 'Mt. Bingushi' situated between 'Second Castle Door' and 'Third Castle Door' whereby it is considered that a major facility such as lodging houses for Sakimori (soldiers garrisoned at strategic posts in Kyushu in ancient times) existed in that area.
After losing the Battle of Hakusukinoe in 663, Wakoku (later Japan) built defense facilities in various western regions to secure the country against Tang (China) and Silla (Korea). As part of the said security measure, Kaneda-jo Castle was built to become the forefront to defend the Korean Peninsula in 667.