본고에서는 거창 지역의 성지(城址)와 거열산성(사적) 및 분산성을 검토한 바탕에서 거열성과 거열주 만흥사산성을 비정하고 그 성격을 규명해 보았다. 거열성은 거열(거 타) 지역의 중심적인 성이라 할 수 있으며, 따라서 거창의 중심지에 위치한 고대 산성인 분산성이 그것이었을 가능성이 크다. 그곳은 가야 때부터 중요한 지점이었던 것으로 판 단되며, 여기에 성이 축조되어 거열성이라고 지칭되었을 것이다. 거열주 만흥사산성은 건흥산성, 즉 거열산성 2차성에 비정된다. 거열산성 1차성은 6 세기 중엽부터 군사 시설로 활용되었을 가능성이 있지만, 그것을 거열성이라고 하지는 않았을 것이다. 신라는 당과의 전쟁 도중에 여기에 새로 만흥사산성을 축조하였다. 신라 는 가야 지역을 차지한 뒤 한강 유역과 같이 본격적으로 축성하지 못하였는데, 그 결과 백제에게 이 지역을 내주기도 하였다. 문무왕 13년(673) 만흥사산성의 축조는 당군과 대치하는 상황에서 기존에 뚫렸던 함양-거창-고령 루트를 보완, 방어하기 위한 조치였 다고 판단된다. 본고에서는 문헌에 나오는 거열성과 거열주 만흥사산성을 일관성 있게 비정하고자 하였다. 그 논리는 단순한데 거열성과 거열주 만흥사산성은 마치 한산성(이성산성)과 한산주 주장성(남한산성)이 다른 것처럼 다르게 봐야 한다는 것이다. 앞으로 문헌에 나 오는 성을 성지(城址)에 비정하는 것이 좀 더 체계적으로 이루어졌으면 하는 바람이며, 이를 통해 고대 성의 성격과 활용에 대해 구체적으로 논의할 수 있기를 기대한다.

With the accumulations of outcomes from archaeological excavations of mountain fortress of three kingdoms period, there have been studies about time-periodic territory range of mountain fortress, difference in the way(method) of construction, defence system and so on from various points of view. This is an empirical study on the construction method of the valley part of stone fortress. First of all, it is required to secure large quantity of fresh water for those who lived at mountain fortress. Especially when builders of fortress construct a fortification at the valley part of stone fortress, in advance they must sufficiently consider several options including the establishment of sustainable water resources. First, when it comes to build a fortification on a ridge[or a slope] of a mountain, you have only to consider a vertical stress. However, when it comes to build a fortification at the valley part of a mountain, You must have more sufficient preparations for the constructing process. Because there are not only a vertical stress but also a horizontal pressure simultaneously. Second, a fortification of mountain fortress built by using unit building stone is a structure of masonry construction like brick construction, and the valley part of it is where the construction of the fortification begins. Third, when it comes to build a fortification at the valley part of a mountain, it seems that they use a temporary method such as coffer dam in oder to prevent the collapse of the fortification due to heavy rain. Furthermore, in response to a horizontal pressure a fortification is built by the way of its plane make an arch, or by piling up the soil with the plate method(類似版築) and earthen wall harder method(敷葉) they increase cross-sectional area of the fortification and its cutoff capacity. In front direction they put the reservoir facility for the fear that the hydraulic pressure and earth pressure are directly transmitted to the fortification. The process of constructing the fortification at the valley part of a mountain is done in the same oder as follows; leveling of ground(整地) ⇨ construction of coffer dam ⇨ construction of the fortification between the both banks of the valley ⇨ construction of the fortification at bottom part of spill way(餘水路) between the both banks of the valley ⇨ construction of spill way(餘水路) & reservoir facility ⇨ construction of the fortification at upper part of spill way between the both banks of the valley. Coffer dam facility seems to be not only the protection device on occasion of flood but also an important criterion to measure the proper height of spill way or tailrace(放水路). This study has a meaningful significance in that it empirically examines the method of reduction of the horizontal pressure which the fortification at the valley part of a mountain takes, the date the construction was done, and wether the changes in climate such as heavy rainfall influence the process of construction.