The largest mound in the Somanouchi group and a National Historic Site.
Finds & research
Scattered slabs on the rear summit suggest a pit chamber. A 1987 investigation found the outer embankment and three burials; one haniwa coffin is thought to reuse haniwa originally erected on Nishiyama Kofun.
Two views on the occupant
Archaeological view
An approximately 190m mound (about 182m in the 1927 designation record) at Somanouchi, Tenri. Only its lowest tier is square-fronted and square-backed; the upper tiers are keyhole-shaped, an unusual form. Tenri City describes it as Japan’s largest square-fronted mound. Its haniwa date it to the Early Kofun period.
Imperial Household Agency view
This is not an Imperial Household Agency mausoleum. It was designated a National Historic Site on 8 April 1927 and since 2018 has formed the Somanouchi Kofun Group historic site together with Nishinorikura Kofun.
Field notes
Follow Tenri City guidance and the historic site’s public boundaries. Do not enter school property or private land without permission.