Karatsu, Saga
Due to its proximity to mainland Asia, Karatsu has long been known as a stopover to Korea and China.Under ritsuryō, the current city area was part of the Hizen Province. In 1591, on the coast of the northern part of the city (formerly the town of Chinzei), Nagoya Castle was constructed. The following year, it became the location from which the Imjin War was launched by Toyotomi Hideyoshi. In the middle of 1593, Terasawa Hirotaka created the Karatsu domain and began governing it. In 1602, replacing Nagoya Castle, Karatsu Castle was constructed in what is now the heart of Karatsu. The tower of Karatsu Castle was built in 1966 .
Nanao Castle
Nanao Castle regarded as one of the five largest medieval mountain castles in Japan along with Kasugayama Castle (Niigata Prefecture), Odani Castle and Kannonji Castle (Shiga Prefecture), and Gassan Toda Castle (Shimane Prefecture). It is located along the upper slopes of Shiroyama mountain, a 300 meter height south edge of modern city of Nanao and consisted of several enclosures, each with stone ramparts and dry moats. The central enclosure was at the top of the hill, and could only be reached by passing through the enclosures assigned to important vassals of the Hatakeyama, which completely surrounded the central enclosure on several concentric levels on the lower slopes. The total size of the fortifications exceeded one square kilometer.