On May 15, 1967, the Silla Oak investigation team announced that they had discovered the tomb of King Munmu in Silla.
According to the Samgungnyusa (The Heritage of the Three States), King Munmu left a will that if he cremated after he died and buried it in the East Sea, he would become a dragon and prevent the Japanese invasion of the East Sea.
It is located off the coast of Bonggil-ri, Munmudaewang-myeon, Gyeongju-si, Gyeongsangbuk-do.
This rock, called Daewangam, is a natural rock in the sea close to the beach, and was designated as Historic Site No. 158 in 1967.