Chihaya Castle was a Japanese castle located in Chihaya-Akasaka, Minamikawachi District, Osaka Prefecture. It is designated as a National Historic Site. It was built by Kusunoki Masashige during the late Kamakura period and the period of the Northern and Southern Courts. It is a linked-ring mountain castle, said to have boasted strong fortifications, surrounded on all sides by cliffs. It is also known as Kongozan Castle and is one of the seven Kusunoki castles. This product is a set of a castle stamp and an explanatory booklet. In the late Kamakura period, Kusunoki Masashige, who sided with Emperor Go-Daigo to overthrow the shogunate, built a castle complex in the Kongozan area, consisting of Akasaka Castle (Shimo-Akasaka Castle) and Kusunoki Castle (Kami-Akasaka Castle), among others. Chihaya Castle was a tsume-shiro (a castle built as a last line of defense) built behind Kami-Akasaka Castle, the main castle. It is a mountain castle that utilizes the Chihaya River valley and is surrounded by cliffs on three sides, with Mount Kongo behind it, making it a strategically important location. It consists of 13 kuruwa (walled enclosures) arranged on the ridge and 9 kuruwa arranged on the ridgeline connected to the ridge. In January 1333, the shogunate army of 200,000 troops began its advance, and Akasaka Castle fell. Kusunoki Castle endured a month-long siege but fell due to lack of water. Only Chihaya Castle, defended by about 1,000 people, remained. However, the defenders employed ingenious tactics such as throwing down large stones and trees and firing arrows, as well as conducting night attacks and a relentless guerrilla war, resulting in numerous casualties for the attacking forces. The siege lasted for 100 days, and while the shogunate army was pinned down at Chihaya Castle, Nitta Yoshisada raised an army, leading to the downfall of the Kamakura shogunate. Later, in 1392, it was attacked by Hatakeyama Motokuni of the Northern Court, and Kusunoki Masakatsu, Masashige's grandson, defended it but the castle fell and was abandoned.