巨濟 古縣邑城은 朝鮮前期에 築造된 沿海邑城으로서 그 構造나 築造手法이 朝鮮 前期 에 築造된 城郭의 築城手法을 理解하는데 있어서 중요한 資料가 되는 것이다. 특히 古縣邑城은 朝鮮 文宗 1年(1451)이라는 築城時期의 絶代年代를 아는 朝鮮 前期의 典型的인 沿海邑城으로서 平地城 및 山城과는 달리 丘陵의 末端部와 平地를 이용하여 築造한 平山城으로 築城新圖 頒布以後에 築造된 城이며 太宗과 世宗朝에 一貫되게 維持되어온 沿海邑城의 築城의 마무리 단계에 築造된 城으로서 朝鮮 前期 沿海邑城의 築城에서 蓄積된 築造技術을 압축해서 볼 수 있다는 점에서 築城史的 重要性이 있다고 할 수 있다. 古縣邑城은 1991년 東亞大學校博物館에 의해 北壁과 西壁의 一部가 調査되었으며, 또한 2004년에는 東門址와 東壁 垓字의 일부가 조사되었다. 이 조사에서 東門址 甕城과 垓字 및 濠岸石築과 垓字내 木익 그리고 通行施設인 陸橋部가 확인되었다. 또한 여타의 邑城 平面플랜과 달리 船形의 독특한 平面플랜으로 축조되고 있는 것으로 확인되고 있으며 이것은 船形이라는 하나의 築城패턴이 존재함을 시사한다고 할 수 있다. 또한 垓字 조사에서는 門址와 體城部의 垓字 간격이 1:0.5의 비율로 나타나고 있다. 이것은 體城部와 垓字와의 간격이 門址와 垓字 사이에서는 半으로 감해져서 축조되고 있는 것이 일관되게 지켜지고 있는 것이라고 할 수 있겠다. 다음으로 고현읍성 해자의 上下部 幅의 比率이 1:1.5 비율로 유지되어 축조되고 있는 것을 확인 할 수 있었다. 그리고 古縣邑城의 垓字에서 확인된 出入施設들은 東萊邑城에서 확인되는 木材橋脚과 더불어 적어도 朝鮮前期에는 木製架橋 내지 釣橋의 형태를 유지하였다가 土石을 이용하여 陸橋部의 형태로 점진적인 변화를 보인 것의 단서로 생각할 수 있겠다. 따라서 南海岸地域 沿海邑城의 하나인 古縣邑城의 垓字의 경우는 通典에 기록된 規式과는 일치하지 않지만 비교적 同一한 規式에 의해 築造되었다고 할 수 있겠다. 이와 같은 垓字를 設置한 古縣邑城의 築造背景으로는 巨濟島의 경우 南海를 거쳐 서쪽으로 進出하는 海路상의 중요한 길목으로서 일찍부터 認識되어 大倭寇防禦戰線의 戰略的 要衝地로서의 役割을 수행하기 위해 邑城을 築造하였음을 알 수 있다. 더욱이 巨濟島에서는 古縣邑城을 비롯한 沙等城, 烏良城, 玉浦鎭城, 加背梁城 등 各種 城址가 확인되는 것만도 24개소에 이르고 있으며 이와 같은 城址의 配置關係를 통해서도 巨濟島 地域의 戰略的 重要性은 충분히 傍證되는 바이다. 더구나 古縣邑城이 築造되던 時期에 상당수의 城郭들이 이미 築城되어 있는 것으로 미루어 보자면 이 城郭들의 築造背景 역시 巨濟島 地域이 가지는 軍事的, 戰略的인 價値에 기인하는 것이라 할 수 있겠다. 따라서 이와 같은 背景에 의해 築城된 古縣邑城의 築城樣相을 把握하는 것이야말로 朝鮮時代 沿海邑城의 築城에 內包된 軍事戰略 및 當代의 爲政者들의 愛民思想과 統治哲學의 斷面을 把握할 수 있는 하나의 端緖를 提供할 수 있을 것으로 사료된다. 또한 硏究가 부족한 朝鮮時代 沿海邑城의 類型分類와 城郭防禦施設의 한 단면을 파악할 수 있는 귀중한 자료로서 축성사적 그 의미가 크다고 할 수 있겠다.

The Gohyon eup fortress in Geoje was built in the former period of the Joseon dynasty, and so its structure and construction method is a very important material to understand the construction method of fortress of those days. Especially, in the case of the Gohyon eup fortress, the typical coastal eup fortress, its absolute built date is known to us as the first year of Munjong of the Josoen dynasty (1451), and it is a flat & mountain fortress using the terminal part of hill and flat ground which can be contradict to those of the flat ground fortresses and the mountain fortresses. Also it was built after promulgating the new plan of construction fortress and built at the end of the stage of coastal fortress plan which had been progressed constantly from the age of the king Munjong to Sejong. So it has value in the history of fortress construction as in the respect of reviewing construction skill that had been conserved from constructing fortress work through the former period of the Joseon dynasty. Gohyon eup fortress was investigated its part of those north wall and west wall by the members of Donga university museum in 1991 and in 2004, the part of east lineage and the moat of east wall were investigated. Through this investigation they identified the east lineage, the moat, the stone sheath, the wooden sticks in moats, and the land bridge the passing facility. As a result of this investigation it was confirmed that the flat plan for Gohyon eup fortress had a trait of special shape of vessels contradict to the other flat plans for eup fortress, and this suggests that there existed a vessel shape as a construction pattern. And also in the investigation of moats it was found that the space of the lineage and the moat of fortress wall has the percentage of 1: 0,5. This suggests that there was a kind of building policy to keep a space between lineage and moat as much as the half of the fortress and moat. And then they identified that in case of the moat of Gohyon eup fortress, the percentage of the width of the upper part and lower part had consistency of 1:1.5. The identified entrance facilities in the moat in Gohyon eup fortress give us a clue that they had conserved their shapes as wooden bridge at least until the former period of the Joseon dynasty like as the identified wooden bridge in Dongrae eup fortress and changed slowly to the shape of the part of a land bridge using mud and stone. Therefore in the case of the moat of Gohyon eup fortress that is the one of coastal eup fortress in the south part, even though it was not built according to the rule described in Tongjeon, we could say that it was built somewhat with the same rule. As a background of constructing Gohyon eup fortress which has that type of moat, we can suppose that it was from the policy to have it a role of important strategic area as a front defence battle line, because in the case of Geoje island it was perceived as an important way of sea from the south sea to the west. More over, in Geoje island there are at leat 24 found fortresses like as Sadeung fortress, Oryang fortress, Okpo fortress, and Gabaeryang fortress including Gohyon eup fortress and this has sufficient proof of its strategic significance. In addition as viewing the numerous fortresses which had already been built before the presence of the Gohyon eup fortress, we can suppose that those fortresses` background is also from its military and strategic importance of the area. Therefore grasping the construction style of Gohyon eup fortress which has the base of those background is considered to supply a clue to understand military strategy, politician`s love for people, and an aspect of governing philosophy of those days. This study has also a great significance as a material for understanding the history of constructing fortress because it can supply a data for classifying types of coastal eup fortress and grasping an aspect of defence facilities of fortress of the Joseon dynasty which is still in need of study.