The group's only keyhole mound, preserved in Sakurabasama Historic Park — the chieftain who preceded the coffin culture of Kabutoyama and Maruyama.
Finds & research
Small corridor chamber (4.3m) in the front section; Haji, Sue, and Korean-style pottery.
Two views on the occupant
Archaeological view
A 50m keyhole mound — the only one in the Oiwayama group — of the early 6th century. The rear burial is unknown, but a small corridor chamber (4.3m) in the front section yielded Haji, Sue, and Korean-style pottery, hinting at immigrant connections.
Imperial Household Agency view
Not designated by the IHA. Part of the National Historic Site "Oiwayama Kofun Group" (added 1985).
Field notes
In Sakurabasama Park (9:00–17:00, closed Mondays, free), together with Kabutoyama (id:592) and Maruyama (id:600).