Kukuchi-jo Castle (a ancient mountaintop castle in Kumamoto Prefecture) (鞠智城)

Kukuchi-jo (also known as Kikuchi-jo) Castle is one of the ancient mountaintop castles (Korean-type mountaintop castle). It was located from Yamaga City, Kikuka Town, (former Kikuka Town, Kamoto County) to Kikuchi City in Kumamoto Prefecture. It wa a castle different from the Kikuchi clan's 'Kikuchi-jo Castle' (Kikichi hon-jo [Kikuchi Main Castle]) in Waifu, in Kikuchi City.


The name of the castle first appeared in the authentic history in the article of the renovation during the era of Emperor Monmu (in 698), however, the document has no description about the year when it was constructed and even now it remains unknown. However, because in the latter half of the seventh century the Japanese army was defeated by the Allied Forces of Tang Dynasty and Silla Kingdom in Hakusukinoe (Baekgang jeontu) in the Korean peninsula, the castle may have been built as a militant stronghold against their attacks.

From the description in the 'Rikkokushi' (the Six National Histories), the materials of the ancient history, and from the unearthed Paekche-type roof tiles and so on, Kikuchi-jo Castle is thought to have been constructed under the guidance of noblemen exiled from Paekche, therefore a bronze standing statue of Bosatsu (Bodhisattva) which is presumed to have been carried in by Paekche noblemen was excavated from the ruins.

It is one of the six castles under the jurisdiction of Dazaifu and thought to have been a castle prepared for a contingency as an army assembly area of Ono-jo Castle (Chikuzen Province) and Kii-jo Castle. The area of the castle keep is 55 hectares and that of outer edge 65 hectares.

In 1959 it was designated as prefectural designated ruins as 'the site of the Castle according to tradition.'
Since the start of excavation research in 1967, 72 building foundations including an octagonal building which was rare at that time (there are similar remains in Niseiyama-jo Castle in the South Korea) have been found.

In 1994 preparation as Historic Park Kikuchi-jo Castle began. In 1997 rice warehouses in Azekura-zukuri (an architectural style in which the sides of the building are made by placing logs across each other) and barracks were restored to be opened to the public, as well as an octagonal drum tower was in 1999. In 2004 it was designated as a national historic site.