The largest mound in Otokuni, built in the early 5th century. In 1980, about 700 iron weapons were found in a deposit facility in the front. The principal rear burial remains unconfirmed because of a cemetery.
Finds & research
A deposit facility in the front yielded about 700 iron weapons, including 146 straight swords, 11 iron swords, 52 daggers, and 472 arrowheads.
Official status & archaeological view
Official status
Designated a National Historic Site in 1981, it became a component of the National Historic Site Otokuni Kofun Group in 2016. Its finds became Kyoto Prefectural Tangible Cultural Properties in 1999.
Archaeological view
An approximately 128m three-tiered keyhole mound at Shoryuji and Kugai 2-chome, Nagaokakyo. Its rear is about 78.6m across and 10.4m high, its front about 78.6m wide and 7.6m high, with a roughly 30m-wide moat. Stone facing and haniwa rows are documented.
Field notes
The site is open as Igenoyama Kofun Park; follow current Nagaokakyo City guidance.