are megalithic
tomb
A tomb ( grc-gre, τύμβος ''tumbos'') is a :wikt:repository, repository for the remains of the dead. It is generally any structurally enclosed interment space or burial chamber, of varying sizes. Placing a corpse into a tomb can be ...
s or
tumuli
A tumulus (plural tumuli) is a mound of earth and stones raised over a grave or graves. Tumuli are also known as barrows, burial mounds or ''kurgans'', and may be found throughout much of the world. A cairn, which is a mound of stones buil ...
in
Northeast Asia
Northeast Asia or Northeastern Asia is a geographical subregion of Asia; its northeastern landmass and islands are bounded by the Pacific Ocean.
The term Northeast Asia was popularized during the 1930s by American historian and political scienti ...
. ''Kofun'' were mainly constructed in the
Japanese archipelago
The Japanese archipelago (Japanese: 日本列島, ''Nihon rettō'') is a archipelago, group of 6,852 islands that form the country of Japan, as well as the Russian island of Sakhalin. It extends over from the Sea of Okhotsk in the northeast to t ...
between the middle of the 3rd century to the early 7th century CE.
[岡田裕之「前方後円墳」『日本古代史大辞典』大和書房、2006年。]
The term is the origin of the name of the
Kofun period
The is an era in the history of Japan from about 300 to 538 AD (the date of the introduction of Buddhism), following the Yayoi period. The Kofun and the subsequent Asuka periods are sometimes collectively called the Yamato period. This period is ...
, which indicates the middle 3rd century to early–middle 6th century. Many ''kofun'' have distinctive keyhole-shaped mounds (). The
Mozu-
Furuichi kofungun or tumulus clusters were inscribed on the
UNESCO World Heritage List
A World Heritage Site is a landmark or area with legal protection by an international convention administered by the United Nations Educational, Scientific and Cultural Organization (UNESCO). World Heritage Sites are designated by UNESCO for h ...
in 2019, while
Ishibutai Kofun
is a stone ''kofun'' or tumulus of the Asuka period in the east of Shimanoshō, Asuka, Nara Prefecture, Japan. The kofun is believed to be the tomb of Soga no Umako. It occupies an area of , and is the largest known megalithic structure in Japan. ...
is one of a number in
Asuka-Fujiwara
Asuka-Fujiwara: Archaeological sites of Japan’s Ancient Capitals and Related Properties is a cluster of archaeological sites from in and around the late sixth- to early eighth-century capitals of Asuka and Fujiwara-kyō, Nara Prefecture, Japan. ...
residing on the