A square mound 50m on a side and 8.5m high, built south of the Nakatsuhime mausoleum alongside Suketayama and Yashimazuka Kofun. The three align their southern edges and share a moat, an unusual arrangement; the moat is preserved underground. It is dated to the middle phase of the Middle Kofun period. The Imperial Household Agency administers it as a satellite of the Nakatsuhime mausoleum, and it is a constituent monument of the Mozu-Furuichi Kofun Group World Heritage Site, inscribed in 2019.
Finds & research
Cylindrical haniwa have been recovered from the moat shared with Suketayama and Yashimazuka. In 1978 that moat, between Nakayamazuka and Yashimazuka, gave up two huge wooden sledges known as shura (Important Cultural Property): a large one 8.8m long and a small one 2.8m, thought to have been used to haul sarcophagi and chamber stones during the building of the mounds. The burial facility and grave goods are uninvestigated as a designated satellite tomb.
Official status & archaeological view
Official status
Nakayamazuka is managed by the IHA (with Yashimazuka); only Suketayama is a national historic site.
Attribution (jitei): the Imperial Household Agency's determination of whose tomb it manages — separate from heritage designation.
Archaeological view
The occupant is unknown; it is dated to the middle of the Middle Kofun period by the Agency for Cultural Affairs and to the first half of the 5th century by the official World Heritage website. A 1999 Fujiidera City Board of Education bulletin, however, presents two views on the date of the Mitsuzuka trio: the 5th century, based on haniwa from the moat, and the 7th century, extending observations of Suketayama Kofun to Nakayamazuka and Yashimazuka. It stands at the centre of the Mitsuzuka trio and, together with Yashimazuka, is the largest of the three at 50m.
Field notes
The official World Heritage site gives about a 6-minute walk south from Kintetsu Hajinosato Station (Minami-Osaka Line). The mound is managed by the IHA and cannot be entered; view it from the surrounding streets.