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 .
Toyama Castle
In the 1550s, the Jinbō clan overwhelmed the Shiina; however, the Shiina made an alliance with Uesugi Kenshin, who captured Toyama Castle in 1570 after a fierce back-and-forth struggle. The leader of the Jinbō clan fled to Oda Nobunaga. The Uesucgi plan placed Kojima Motoshige, a former retainer of the Jinbō, in charge of the castle as castellan, and he suppressed an attack by the "Ikkō-ikki" in 1571. Due to a plot by Takeda Shingen, the Shiina then revolted against Kenshin, but were defeated. After Kenshin's death, Nobunaga extended his power into the region, placing Jinbō Nagatsumi back in charge of Toyama Castle in 1578. However, due a revolt by his retainers Jinbō Nagatsumi lost control of Toyama Castle in 1581. Nobunaga was unforgiving of this incompetence, and installed his general Sassa Narimasa in his place. The Jinbō clan then disappears from history (with the major exception of the place name, Jinbōchō, Tokyo after a surviving clan member who entered the service of Tokugawa Ieyasu). Under Sassa Narimasa, the castle was greatly expanded in size, and new moats and towers were added. Narimasa also began a series of flood control works which gradually transformed the area surrounding the castle from a marsh to rich rice lands.