“The Western Capital”, An Ancient International City With A Rich 1300-Year History, Registered As A Japan Heritage Site

Kii-jo Mountain Fortress were once an ancient mountain fortress built on the eastern peak of Mount Kizan located south of Dazaifu, and with earthworks such as those at Sekiya and Toregi built at the base of the mountain, it is believed to have protected Dazaifu to the south. The earthworks were used as fortress walls stretching 4 km long, and there are the ruins of the fortress gate, the water gate, and the cornerstones of nearly 40 buildings left behind. The southernmost water gate is built with one of the longest water ditches among all ancient mountain fortress, and three smaller water ditches have been discovered alongside it. Many warehouses were built during the Nara period, and the role of the fortress started to change into a place to stockpile rice and other grains in preparation of famine or disaster, and it also began serving as a place of cultural exchange, with the Governor-general of Dazaifu Otomo no Tabito ascending to the top of the fortress in early summer with officials from Dazaifu or the capital to exchange poems.

These are the remains of a gate built on earthworks at the entrance to Kii-jo Fortress, where two foundation stones for the gate can still be seen in an area where the earthworks have broken off. The foundation stone is carved with round holes where the door shafts would have been inserted, from which it is estimated that there were double doors opening from the center that had a frontage of about 1.95 meters. The Northeast gate is located due south of the Dazaifu Government Building and is one of the four gates currently assumed to have existed at Kii-jo Fortress, and on the way there you can see the ruins of Ono-jo Fortress (on Mount Shioji) to the north in the distance. It’s easy to picture how people would travel in those days or how people bringing goods from the warehouses in the fortress would be checked by guards at the gate.