Imperial Household Agency: Kochi-no-Shinaga-no-Nakanoo-no-Misasagi (Mausoleum of Emperor Bidatsu)
Also known as: Okushiro Kofun
Location
Taishi, Osaka
Shape
Keyhole-shaped mound
Mound length
93 m
Period
6th c.
Designation
IHA-managed tomb
IHA designation
Managed by the IHA (mound closed to the public)
Overview
A keyhole mound in Taishi, designated by the Imperial Household Agency as Emperor Bidatsu's mausoleum. Taishi Town dates its construction to the first half of the Late Kofun period, while Kashiwara City gives the late or end of the 6th century.
Finds & research
Haniwa have been collected nearby. A horizontal stone chamber remains an inference; details of the interior and grave goods are unknown.
Official status & archaeological view
Official status
The Imperial Household Agency designates and manages it as Kochi-no-Shinaga-no-Nakanoo Mausoleum of Emperor Bidatsu, the 30th emperor, and classifies it as a keyhole mound.
Attribution (jitei): the Imperial Household Agency's determination of whose tomb it manages — separate from heritage designation.
Archaeological view
Taishi Town describes it as about 93m long and the only keyhole mound in the Shinaga valley, with a dry moat. Haniwa collected nearby lead the town to date it to the first half of the Late Kofun period. The Nihon Shoki says he was buried in his mother Empress Ishihime's tomb, but the occupants have not been archaeologically verified.
Field notes
The Imperial Household Agency gives access as about a nine-minute walk from the Bidatsu Tenno-ryo-mae bus stop. Worship hours are generally 8:30–17:00. The goryoin (mausoleum seal) is kept at the Furuichi Mausolea Office in Habikino, Osaka, where visitors can use it free of charge (reception 8:30–17:00; staff may be unavailable on weekends, holidays, 29 Dec–3 Jan and some other days).