These are the tombs of King Adalla (r. 154-184), King Sindeok (r. 912-917), and his son King Gyeongmyeong (r. 917-924), the 8th, 53rd, and 54th rulers, respectively, of the Silla kingdom (57 BCE-935 CE). They are all descendants of the Bak Clan.
King Adalla worked to improve domestic affairs, such as by constructing roads, and also exchanged envoys with Japan in the year 173. Kings Sindeok and Gyeongmyeong reigned during the decline of Silla. They ruled only over the Gyeongju area, as the Later Baekje and Later Goguryeo kingdoms had already taken over most of the Silla territory.
The tombs, from front to back, belong to Gyeongmyeong, Sindeok, and Adalla. The tomb of King Sindeok was robbed in 1963. The walls inside the stone chamber in the tomb mound were painted like a folding screen painting.