Songsan-ri Tumuli Site located on the south slope of Mount Songsan, which surrounds Gongju, Southern Chungcheong Province, the old capital of the Baekje Kingdom, are said to be of kings who reigned over Baekje between 475 and 538. After the transfer of the capital from Hanseong (the present Seoul) to Woongjin (present-day Gongju City) during the reign of King Munju (r. 475-477) - King Samgeun (r. 477-479), King Dongseong (r. 479-501), and King Muryeong (501-523) used Woongjin as their capital for 63 years. This is because Goguryeo Kingdom led by King Gwanggaeto the Great conquered Hanseong in 395 CE, during the reign of King Asin. Following the decline of Baekje Kingdom, King Seong (r. 523-554) then transferred the capital to Sabi (the present Buyeo County).
These tombs seem to have been located here in keeping with the principles of geomancy. The site is protected by Gongsan Fortress on the east, the Geum River on the west, and Mount Gyeryong on the south. The tomb structures are of two types: stone chamber tombs and brick chamber tombs. There are seven tombs in all. Four tombs located in the back row and one in the front row (Tomb No. 5) are included in the stone chamber category. The other two tombs in the front row (the tomb of King Muryeong and Tomb No. 6) are in the brick chamber category. The tomb of King Muryeong (Tomb no. 7) was discovered accidentally in 1971 and made an epochal contribution to the study of Baekje culture.