The tumulus is located on the north side of Ioi village. It is a circular earth mound with a diameter of about 35 meters and a height of 4 meters. An emergency investigation was carried out because the burial facility was accidentally discovered during the construction of cenotaph in 1954. The investigation confirmed that the tumulus had already been looted, but some mirrors, iron swords, cylindrical bronze ware were unearthed. It is estimated to be the tumulus of the early 5th century.