The Aotsuka Kofun is located in the southern part of Inuyama, in western Aichi Prefecture. It is one of tumuli which once formed a
kofun cluster in the surrounding area (most of which have now been destroyed).
Archaeological excavations have been conducted in 1979 and from 1995 to 1998. The tumulus is a , which is shaped like a keyhole, having one square end and one circular end, when viewed from above. It has a total length of 123 meters and is orientated to face southwest. It consists of a three-tiered posterior circular portion with a diameter of 78 meters and height of 12 meters, and a two-tier trapezoidal anterior portion, with a width of 62 meters, length of 45 meters and height of seven meters. A surviving portion of a moat is on the west side of the tumulus, and on the east side a raised embankment for crossing the now vanished portion of the eastern moat has also survived. An unusual feature of this
kofun is the presence of a rectangular mound on the far end of its anterior portion, which may have been a ceremonial platform. The tumulus was formerly covered in
fukiishi across its entire surface, and had rows of cylindrical and drum-shaped
haniwa. It is believed to have been built in the middle of the 4th century in the early Kofun period. The
kofun is associated with the
Ni-no-miya of
Owari Province, , which is located 3.5 kilometers to the east. The shrine claims that the
kofun is the grave of its
kami, . During the
Sengoku period, the tumulus was fortified as a castle by the forces of
Toyotomi Hideyoshi during the 1584
Battle of Komaki and Nagakute. The site is now open to the public with the exterior of the tumulus restored to its appearance at the time of construction, with a row of replica pot-shaped
haniwa as part of the Aozuka Kofun Historical Park, which also has an on-site museum. It is located about a 30-minute walk from
Gakuden Station on the
Meitetsu Komaki Line. ==Ōagata Shrine==