★ World Heritage Sakai, Osaka Keyhole-shaped mound

Nagayama Kofun

LocationSakai, Osaka
ShapeKeyhole-shaped mound
Mound length100 m
Period5th c.
World HeritageMozu-Furuichi Kofun Group (UNESCO)

Overview

A 100m keyhole-shaped satellite mound northeast of Daisen Kofun. Among the Mozu group's satellite tombs, this is one of the largest. The three-tiered mound with moat represents a typical large-scale satellite of the 5th century. The satellite tomb system (baicho) developed around the great royal mounds of the 5th century, and more than a dozen satellite mounds are documented across the Mozu and Furuichi groups combined.Constituent monument of the "Mozu-Furuichi Kofun Group" UNESCO World Heritage Site (2019). Managed separately from the main Daisen Kofun enclosure as a "detached" IHA site. The satellite tomb system (baicho) is attested across ancient East Asia and concentrates around the great Japanese royal mounds of the 5th century. The presence of satellite tombs reflects both the power of the great kings and the ancient belief that close attendants should rest beside their lord in death. The name "Nagayama" (Long Hill) is an old place name in the area and may relate to the mound's elongated hillock profile.

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
A keyhole mound considered a satellite of Daisen Kofun (the designated Emperor Nintoku mausoleum). 100m long, three-tiered construction. Dated to the 5th century; thought to have been built concurrently with or shortly after the main mound. The occupant is presumed to have been an important figure closely connected to the main occupant of Daisen Kofun—perhaps a consort, prince, or chief retainer—but cannot be specifically identified. Among the Mozu group's satellite mounds, this is a relatively large keyhole mound.
Imperial Household Agency view
Managed by the IHA as a "hirokuchi" (detached satellite) of the Nintoku Mausoleum. A baicho is a supplementary mound adjacent to the main tomb, housing attendants, kin, or retainers of the principal occupant. "Hirokuchi" indicates it is not directly adjacent but in a nearby separate location.
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Sources

宮内庁百舌鳥・古市古墳群 公式サイト

Related kofun

Daisen Kofun (525m) Kamiishizu Misanzai Kofun (365m) Haji Nisanzai Kofun (300m) Gobyoyama Kofun (203m) Tadeiyama Kofun (148m) Itasuke Kofun (146m)
← Itasuke Kofun Magotayuyama Kofun →