300m long (7th nationally, 3rd in Mozu group). 3-tiered, with the front section rising to 25.9m — wider and taller than the rear circle, a late trait in keyhole-mound design. Sakai City and the IHA have investigated the site; Sakai City excavated the inner moat in 2012–2015. It stands at the south-eastern edge of the Mozu group, in Mozunishinocho, Kita-ku, Sakai. Constituent monument of the "Mozu-Furuichi Kofun Group" UNESCO World Heritage Site (2019). The IHA manages the mound as a reference site rather than a confirmed imperial mausoleum.
Finds & research
The mound is built in three tiers with projections on both sides of the waist. In the moat east of the rear circle, up to seven rows of postholes (max. ~12m across, some timbers surviving) are thought to mark a timber bridge once thrown over the water, and a further outer moat has been traced and preserved underground. Cylindrical haniwa set edge to edge were found on the first terrace, a large Sue ware jar on the projection, and figural haniwa plus umbrella-shaped wooden haniwa in the moat. The burial facility and grave goods remain uninvestigated.
Two views on the occupant
Archaeological view
Occupant unconfirmed. The 7th largest nationally and 3rd in the Mozu group (300m). Dated to the late 5th century, it may represent the final phase of large-scale mound construction in the Mozu group, following Daisen (early 5th c.) and Kamiishizu Misanzai (beginning of the 5th c.). Excavation in the moat east of the rear circle found up to seven rows of postholes running from the mound slope to the embankment, as much as 12m wide — read as the footings of a timber bridge across the moat, put up at the very end of construction or just after it and removed again after short use in the building work or the funerary rites.
Imperial Household Agency view
Designated as the "Higashimozu Ryobo Sankochi" (eastern Mozu reference site), associated with Emperor Hanzei. A sankochi (reference site) is not recognized as a confirmed imperial mausoleum but is managed in the same manner as one; Sakai City and the IHA have investigated the site.