Construction Period and Characteristics of Polygonal Buildings during the Three Kingdoms to the Unified Silla Dynasty Periods

The polygonal buildings from the Three Kingdoms Period are deemed related to religious buildings associated with temples, namely wooden pagodas. With the investigation of a presumed palace site inside Hwandosanseong Fortress in Ji’an Prefecture of China and Najeong, the well, in the west of Namsan Mountain in Gyeongju, the polygonal buildings are seen as facilities related to national rituals. In addition, there were discussions about their characteristics with the investigation of polygonal building sites in fortresses located in the Hanggang River basin in the Gyeonggi-do region. The examination of polygonal buildings investigated in Korea showed that Goguryeo and Silla chose octagonal buildings and Baekje, dodecagonal buildings during the Three Kingdoms Period. In the Silla region, in particular, octagonal buildings constructed around ancient tombs with stone chamber tombs with a tunnel entrance and rectangular stonework are deemed ceremonial facilities related to tomb rituals. In this light, most polygonal building sites are presumed to have been constructed around the 9th century, the later years of the Unified Silla Dynasty, other than those constructed during the Three Kingdoms Period, and the dates could be presumed with the earthenware excavated in Hanam Iseongsanseong Fortress. It is a building related to rituals as it coexists with the rectangular stonework adjacent to the tombs. In conclusion, polygonal buildings are deemed ceremonial facilities related to national, local, and tomb rituals during the Three Kingdoms to the Unified Silla Dynasty Periods.