It is a true fact that the ancient Buddhist temples of Korea were great, important historical influence revealing the transition and developing stages of all the BUddhist temples in Eastern Asia including China and Japan. Before Mahayana arose within India, the monastery and pagoda were united during the conflict and development of the original Buddhism and pagoda faith. With the arising of Mahayana and the introduction of Buddhist statues, the Buddhist temple and pagoda were in conflict and resulted in separation. With the creation and development of the Mahayana Bodhisattva concept, Hinayana and Mahayana started to show doctrine differences and expressed each others' characteristics relevant to the structure of the temple. As a result, the Buddhist Temple having 1 pagoda spread in China together with Hinayana and Mahayana. The Buddhist temple of Hinayana had its temple and pagoda separated and the Buddhist temple that has a pagoda in front was divided into a form of 1 pagoda and 1 main temple. The temple and pagoda for Mahayana in the form of 1 pagoda and 2 temple, where the main statue of the Buddha may be worshipped from both the left and right hand sides, were separated in the form of 1 pagoda and 3 temples to have its original form again. Mahayana was first introduced into Goguryeo through the routes in the northern region and developed from having 1 pagoda and 2 temples, to having 1 pagoda and 3 temples. China was influenced by the southern regions, which is why Abhidharma was introduced into Baekje. Later on, the importance of Bodhisattva increased and the transition speed of the Buddhist temple having 1 pagoda and 3 temples accelerated, as Buddhism became more popular and as Mahayana flourished. The statue of the Buddha on both sides of the pagoda shall gradually move next to the central temple , and the temple shall form large crowds to not only form a tacit boundary with the pagoda but the expansion of Bodhisattva shall also have a wall or a corridor constructed in between the central, left and right hand side temples to form separate areas, and shall have a pagoda built in front of the temples that worship from both sides. In conclusion, independence shall exist among each Bodhisattva within the Buddhist temple, and the status of the pagoda shall fall and appear as the pagoda on both sides in front of the main Buddha statue.

Korea's stone buildings are varied in their types such as stone pagodas, stone lanterns, stone bridges, stoneworks, etc. These account for more than 30% over the entire cultural properties, but research achievements are lacking compared to wooden buildings. Accordingly, this study aims to identify the shape, role and transition of Tapgu, which had been used to set up boundary at a stone pagoda, one of the stone buildings. The 20th stone pagodas, which have relative accuracy in its forming year, have been studied around national treasure or treasure between 7th century and 9th century. There are a lot of different opinions about the role and meaning of Tapgu, and at this writer's option, Tapgu is defined as follows: First, each structure plays a different role. A structure to pass the load in the upper part to the ground can be seen as a stair or a pedestal, but a structure to form double foundations can be considered as Tapgu. Second, Tapgu can be used to divide areas with stones or stepping stones. As a result, the shape, role and transition of Tapgu is as follows: Firstly, when it comes to its shape, Tapgu includes flagstone type, belt type, double foundation type, compound type. Flagstone type had been used to set up boundary at stone pagodas by using foundation stone, belt type by keeping apart from stone pagodas, and double foundation stone by installing dual foundation stones. Secondly, Tapgu is considered to set up boundary in the case of flagstone and plate stone, and acts like a structure which can prevent surrounding area of stone pagoda from coming up while being stuck around stone pagodas. Belt type was installed only for the purpose of forming boundary. At the bottom, double foundation stone had been used to pass the load in the upper part to the ground in the same way as the foundation stone in the upper part, and the boundaries were set varying the size. Thirdly, when it comes to the transition of Tapgu, flagstone type of boundary stone had been installed in the 7th century, and belt type of boundary stone had been mainly installed in the 8th century. And double foundation stone had been installed in the 9th century. Comprehensively, flagstone type and belt type had been made around the 7th and 8th century when Tapgu was regarded important and stone pagoda started to be built. At the turn to the 9th century, the role of Tapgu had been increasingly losing in the construction of stone pagoda, and foundation stone started to appear.

Through analysing on construction cases of stupa built in A.D. 7,8th, I have researched about these : constructive methods of inner soil of stupa, spatial compositions, characteristics of structures, arrangements of inner soil and etc. And cases analysed are six ; Mireuksajiseoktap(stone pagoda of Mireuksa Temple site), Gameunsajisamcheumgseoktap(three storied stone pagoda of Gameunsa Temple site), Goseonsajisamcheungseoktap(three storied stone pagoda of Goseonsa Temple site), Wolseong nawolliocheungseoktap(five storied stone pagoda in Nawonri, Wolseong), Guksagokseoktap(three storied stone pagoda in Guksa valley), Giamgokseoktap(three storied stone pagoda in Giam valley). Additionally we researched about inner soil of Sacheonwangsaji tapji(basement of stone stupa site in Sacheonwang Temple site) to speculate on composition of Synthetically, the foundation could be divided as core space and outer space. ; the former as structural function and the latter as ornamental function. And the core area could be divided again as center column space and buffer space. The relationship between core spaces and its formation are as belows; First, according to the area of foundation and scale of stone pagoda, formations of core are differed. As the scale of stone pagoda goes bigger, and the area of foundation goes larger, the structure of stone pagoda comprised by center column type and layered-core which endure upper load independently. On the contrary, as the scale of stone pagoda goes smaller, and the area of foundation goes lesser, the structure of stone pagoda tend to use only center column to endure upper part. Second, spatial composition of core area is comprised as two spaces, one which endure upper load and buffer space which absorb side pressure and upper pressure. The buffer space tend to be used in case of those structures which could not endure side pressure or have lots of joint. In some cases, it was located below the cover stone of foundation and gained upper load. And in case that have not gained pressure from side stone, the buffer space are comprised by smalle stone or roof tile to get structural supplement.