The tumulus had a structure on the northeast side, possibly a ceremonial platform, and was originally surrounded by a shield-shaped moat.

In 1967, a Japan Air Self-Defense Force training aircraft crashed next to the kofun, causing considerable damage.

During the restoration work, numerous haniwa were found, some in the forms of horses, people, waterfowl, etc., in addition to the more common cylindrical varieties.

Penetration into the interior of the kofun was hampered by seepage of ground water, and subsequent work was suspended.

Fluorescent X-ray analysis revealed that this pottery had been fired at the Shinohara ancient kiln site eight kilometers to the north.