서산 개심사 대웅전 ( 瑞山 開心寺 大雄殿 )
Although the record written at Gaesimsa Temple states that the temple was built by State Preceptor Hyegam during the Three Kingdoms’ Period in the 5th year of the reign of Queen Jindeok of the Silla Dynasty and the 14th year of the reign of King Uija of the Baekje Dynasty, those are different years, i.e., the former is in 651 and the latter is in 654. Generally, the construction year is believed to be 654, the 14th year of the reign of King Uija of the Baekje Dynasty. According to the record found during the repair work in 1941, Daeungjeon Hall of the temple was repaired in the 15th year of the reign of King Seongjong (1484). The hall after its repair work in 1484 has been preserved well. Daeungjeon Hall of Gaesimsa Temple has 3 rooms in front and 3 on the side. As a gable-roofed building, it has the hall heavily adopting the bracket system, wherein brackets supporting the eaves are found not only on the columns but also between the columns. The basic structure of the hall is different from that of Geungnakbojeon Hall of Muwisa Temple in Gangjin (National Treasure No. 13), which follows the structural style of the “bracket on the column” as was typical in the early Joseon. Daeungjeon Hall is an important cultural asset representing early Joseon's wooden building made in the bracket system.