The core of a terminal-period cluster preserved in Tsurugigaoka Park, Yabu. A single sword proved that the Asuka calendar reached this Tajima valley — a textbook case of a tomb that yielded written evidence.
Finds & research
103 finds incl. the AD 608 inlaid sword (Important Cultural Properties); corridor-type chamber.
Two views on the occupant
Archaeological view
A round mound 12m × 14m with a corridor-type chamber (8.6m, or 9.6m per one source), built around 600. It yielded a sword bearing a bronze-inlaid date of "Boshin year" (AD 608) — one of Japan's few dated blades; the 103-piece assemblage is an Important Cultural Property. A famous case of first-class written evidence from a small mountain-valley tomb.
Imperial Household Agency view
Not designated by the IHA. Part of the National Historic Site "Midani Kofun Group" (1992; mounds 2–5).
Field notes
Always visitable in Tsurugigaoka Park; the finds are periodically shown at the Hyogo Prefectural Museum of Archaeology.