A terminal-period octagonal mound with a two-room side-entry chamber. The discovery of the adjacent Koshitsuka-Gomon Kofun and its position as recorded in written accounts have drawn attention to an imperial-family hypothesis. It became a World Heritage component in 2026.
Finds & research
Finds include dry-lacquer coffin fragments, cloisonné-enamel fittings with a tortoise-shell hexagon design, glass beads, and teeth. The chamber has two rooms, with plaster surviving on the walls.
Official status & archaeological view
Official status
The IHA designates Kurumaki-Kenno Kofun (the Ochi-no-Okanoe Mausoleum) in Takatori as the tomb of Empress Saimei. This mound is a National Historic Site; Asuka Village carried out restoration works from fiscal 2017 and opened it to the public in March 2022.
Archaeological view
A late-7th-century octagonal mound at Koshi, Asuka. Asuka Village gives, on one page, a diagonal of 18.5m and a height of about 4m, and on another, a width of about 22m across opposite faces and a height of 4.5m or more as established by the 2009 investigation; the mound is of rammed-earth construction. Its side-entry chamber was hollowed from a huge tuff-breccia block, divided by a central wall into two rooms, each with a carved coffin platform. Asuka Village states that, on the basis of the mound's location and the teeth found there, the leading view is that it is the joint tomb of Empress Saimei (Kogyoku re-enthroned) and her daughter Princess Hashihito. Kashihara City notes that Koshitsuka-Gomon Kofun, found beside it in 2010, lies just where the Nihon Shoki entry for the second month of 667 (Tenji 6) places Princess Ota's grave, built in front of the joint tomb of Saimei and Hashihito, and calls the mound noteworthy for the question of its occupants.
Field notes
The reconstructed mound and adjacent Koshitsuka-Gomon Kofun are open. Check current Asuka Village guidance for fees, hours, and chamber-viewing conditions.