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 .
Nirengi Castle
Leadership of the clan passed to Norimitsu who had, sometime in the 1490s, secured the alliance of the Saigo clan by marrying the daughter of Saigo Masasada. Norimitsu moved his residence into Nirengi Castle, and oversaw the highpoint of the Mikawa-Toda house, in about 1508. In 1529, 19-year-old Matsudaira Kiyoyasu attacked Imabashi Castle, and after a fierce battle, was able to take it. The day after his triumphal entry, Kiyoyasu turned his attention to other fortifications in the area, including Ina Castle and Nirengi Castle. Through successive intermarriages, the Toda eventually became a branch house of the Matsudaira.