Site of Utena Fort

Utena Fort, also known as Mizushima Fort, was one of more than a dozen medieval strongholds built by the Kikuchi clan to defend the castle town of Waifu. The fortress faced west on the edge of a plateau around 5 kilometers west of the clan’s castle and had an unimpeded view far downstream along the Kikuchi River. This strategic location, along with the additional protection provided by the Uchida River directly beneath the hill, made Utena Fort extremely difficult to invade.

The most famous battle in the fort’s history took place in 1375, when the Kikuchi clan was fighting against the Ashikaga shogunate, the warrior-led central government. The Kikuchi, who only a few years prior had controlled all of Kyushu, had been pushed back to their ancestral lands after successive setbacks at the hands of the Ashikaga general Imagawa Ryoshun (1326–1420).

Seeking to end Kikuchi resistance for good, Ryoshun brought tens of thousands of warriors to the Battle of Mizushima, but was defeated by a force of 2,000 under Kikuchi Taketomo (1363–1407), the newly appointed clan leader who was only 12 years old at the time. Taketomo’s victory delayed Ryoshun’s conquest of Kikuchi, which he nonetheless completed six years later.

※About the Kikuchi clan.（菊池一族とは）

※Other cultural property explanatory boards are also multilingual.（この他の文化財説明板も多言語化しています。）

台城跡

　菊池十八外城の一つで、守山城の西方約５ｋｍの所にあって、菊池一族興亡の歴史を担ってきた古城です。別名水島城とも呼ばれ、標高７４ｍの丘陵上にあり、東北面は遠く八方ヶ岳に連なり、西に木野川、内田川が流れています。

　江戸時代に記された『菊池風土記』によれば、城主は交代制であったとされています。また、菊池川に沿って侵入する敵を打越城と共に挟み撃ち出来る地点にあって、中間に馬渡城、正光寺城、増永城の３城を連ねており、菊池川を制し菊池と山鹿を結ぶ道路の関門でもありました。

　天授元年（１３７５）９月、数万の大軍を率いた探題今川了俊を弱冠１３歳の賀々丸（武朝）が撃破した水島の戦いは特に有名です。なお、明治１０年（１８７７）西南戦争の時には政府軍と薩摩軍が隈府の争奪を巡って激戦を繰り返した場所でもあります。

　南西部の台地中腹の崖に「瀬戸口百穴」といわれる横穴（瀬戸口横穴群）がありますが、南北朝時代当時はここに食糧や武具等を隠しておいたといわれています。