★ World HeritageHabikino / Fujiidera, OsakaKeyhole-shaped moundIHA imperial tomb
Oka Misanzai Kofun
Also known as: Mausoleum of Emperor Chuai
Location
Habikino / Fujiidera, Osaka
Shape
Keyhole-shaped mound
Mound length
245 m
Period
Late 5th c.
World Heritage
Mozu-Furuichi Kofun Group (UNESCO)
IHA designation
IHA-managed (no public entry)
Overview
245m long (3rd in Furuichi group, 16th nationally). 3-tiered mound, 26m high at the rear circle, with double moats and a northeast-facing front section. Though designated as Emperor Chuai's mausoleum by the IHA, its late-5th-century date is incompatible with the 4th-century Chuai, making the Emperor Yuryaku attribution archaeologically compelling. This mound is one of Japan's most cited examples of the gap between IHA designation and archaeological interpretation.Constituent monument of the "Mozu-Furuichi Kofun Group" UNESCO World Heritage Site (2019). The name "Oka Misanzai" combines the local area name "Oka" with "Misanzai" (a phonetic corruption of misasagi, imperial tomb). Emperor Yuryaku (Wakatakeru / King Bu) sent envoys to the Liu Song dynasty in 478 CE seeking military titles, as recorded in the Song Shu and Nan Shi — making him one of the best-documented early Japanese rulers in foreign sources. If this mound is indeed his tomb, it ranks among the most historically important kofun in Japan.
Finds & research
No excavation permitted under IHA mausoleum regulations. Internal structure and grave goods remain unknown. Exterior viewable from public paths.
Two views on the occupant
Archaeological view
Dated to the late 5th century (c.470–490 CE), far too late for Emperor Chuai (a 4th-century figure). Most researchers identify this as the leading candidate for the tomb of "King Bu" of Wa — the king who sent envoys to the Liu Song dynasty of China — equated with Emperor Yuryaku (r. late 5th c.). Scholars including Taro Shiraishi and Fumiaki Imao support this attribution based on haniwa typology, which firmly places construction in the late 5th century.
Imperial Household Agency view
Officially designated "Ega-no-Nagano-no-Nishi-no-Misasagi" (Mausoleum of Emperor Chuai) by the IHA. Emperor Chuai was the consort of Empress Jingu; according to the chronicles he died en route to the Three Kingdoms campaign. Public access is restricted.[IHA Visiting Info] Address: 大阪府藤井寺市藤井寺4丁目 / Access: 近鉄 藤井寺駅から徒歩約14分 / Hours: 原則、8時30分～17時 (open year-round in principle). Stamp storage: 古市陵墓監区事務所.