Tsutagake Castle

In detail

The remnants of stone walls near the summit of Mt. Jo mark the site of Tsutagatake Castle (also known as Akamayama Castle). The castle was built in the thirteenth century by the Munakata family, which ruled the region until the sixteenth century. Remnants of the castle walls visible along the trail up the mountain give an idea of the castle’s size and its former defensive capabilities.

Around 1560, the castle was expanded and fortified to serve as a siege fort, with extensive earthworks such as ridges and moats. The expansion made Tsutagatake Castle the largest castle in the region. It measured 800 meters east to west and 500 meters from north to south, including its earthworks. Based on fragments of iron and other archaeological evidence, blacksmiths likely worked on the castle grounds making arrowheads and other weapons.

The castle survived several attacks from the Otomo family, which controlled much of eastern Kyushu from the twelfth to sixteenth century. In 1586–1587, Toyotomi Hideyoshi’s forces took the castle during his campaign to subdue the daimyo families of Kyushu. Toyotomi (1537–1598) was a powerful warlord and hegemon who completed the sixteenth-century unification of Japan begun by Oda Nobunaga (1534–1582). The Munakata family was ordered to leave the castle following their defeat. Parts of the castle were demolished on Toyotomi’s orders, and the rest fell into ruin.

On a clear day, it is possible to see the sacred island of Okinoshima from the summit of Mt. Jo. Locations with views of Okinoshima are considered yohai, places for worshipping the island from afar. The whole island of Okinoshima is off limits to the general public, so people come to these places to worship.