Wakayama Pref. Keyhole-shaped mound

Otani Kofun

LocationWakayama Pref.
ShapeKeyhole-shaped mound
Mound length70 m
PeriodLate 5th–early 6th c.
DesignationNational Historic Site

Overview

National Historic Site (1978) keyhole mound (70m) in Wakayama City. Kyoto University excavations (1957–1958) yielded Japan's only complete horse helmet (bachū) and numerous Korean-peninsula-influenced finds, all designated Important Cultural Properties. A key Kii-region mound documenting exchange with the Korean peninsula.

Finds & research

Horse helmet (Japan's only complete example), horse armor — horned iron helmet — 21 glass magatama — bronze mirrors — iron weapons (all designated Important Cultural Properties).

Two views on the occupant

Archaeological view
70m keyhole mound (rear circle ~40m dia., front section ~40m wide, 6–10m high). Late 5th–early 6th century. Kyoto University excavations (1957–1958) revealed a horse helmet (the only complete example in Japan) and horse armor, a horned iron helmet, 21 glass magatama, bronze mirrors, and iron weapons — a first-class corpus demonstrating strong cultural exchange with the southern Korean peninsula. The finds are designated Important Cultural Properties. The occupant is presumed to be a 20–30-year-old male elite of the Ki-uji clan.
Imperial Household Agency view
Not an IHA mausoleum. Designated a National Historic Site on 15 November 1978.

Field notes

Follow current on-site guidance for access and transport.

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Sources

文化庁 大谷古墳わかやまの文化財 大谷古墳(和歌山県教育委員会)

Related kofun

Shakano-koshi Kofun (86m) Shimosato Kofun (45m)
← Dainichizan No.35 Kofun Shakano-koshi Kofun →