Shiga's largest keyhole mound, on a ridge-end extending from Mt. Kinugasa in Azuchi, Omihachiman. As one of the earliest great keyhole mounds in Omi, it marks the Yamato court's reach to Lake Biwa's eastern shore. A full-scale replica of the central chamber and copies of the finds are shown at the Azuchi Castle Archaeological Museum.
Finds & research
Three pit-style chambers and two cist coffins. Kiho and deity-beast mirrors, iron swords and arrowheads, farm tools, and haniwa (Kyoto University Museum).
Two views on the occupant
Archaeological view
A keyhole mound ~134m long (some sources 136m; an older figure of 162m persists) — the largest in Shiga. Built in the mid-4th century, with three pit-style chambers in the rear circle and two cist coffins in the front. The central chamber yielded a kiho mirror, a two-deities-two-beasts mirror, iron weapons, and tools (Kyoto University Museum). The occupant may have been a chieftain of the Sasaki-yama lineage or an envoy of the Yamato court. Distinct from the same-named mound in Higashiosaka (id:383).
Imperial Household Agency view
Not designated by the IHA. National Historic Site "Hyotanyama Kofun" (designated 1957).
Field notes
About 25 min on foot from JR Azuchi Station. The mound is walkable, though the chambers are reburied. Usually combined with the Azuchi Castle site and its museum.