磯浜古墳群 | |
![]() Hisagezuka Kofun | |
Location | Ōarai, Ibaraki, Japan |
---|---|
Region | Kantō region |
Coordinates | 36°18′57.60″N140°34′13.33″E / 36.3160000°N 140.5703694°E |
Altitude | 10 m (33 ft) |
Type | kofun |
History | |
Founded | 3rd - 4th century AD |
Periods | Kofun period |
Site notes | |
Excavation dates | 1949, 2011-2021, 2019-2020 |
Public access | Yes (no facilities) |
![]() |
The Isohama Kofun Cluster (磯浜古墳群, Isohama Kofun-gun) is a group of ancient Kofun period burial mounds, located in what is now part of the town of Ōarai, Ibaraki in the northern Kantō region of Japan. Three of the tumuli at this site were designated a National Historic Site in 2020 and three more are under consideration. [1]
The Isohama Kofun Cluster is located in the central part of Ibaraki prefecture, facing the Pacific Ocean, about three kilometers southwest of the mouth of the Naka River. The site is located on a hill and consists of two zenpō-kōen-fun (前方後円墳), which are shaped like a keyhole, having one square end and one circular end, when viewed from above, one "two-conjoined rectangles" type kofun ( zenpō-kōhō-fun (前方後方墳)), two circular-type kofun (empun (円墳)) and two of indeterminate shape. The site once contained many more tumuli, most of which were destroyed due to land development and urban encroachment.
The keyhole-shaped tumuli have been excavated, and over 4100 grave goods were recovered, including two bronze mirrors, iron swords, jade magatama , and jasper tubes, balls and other jewelry, and facsimiles of everyday objects. A number of human remains were also found. The Hisagezuka Kofun, with a total length of 101.4 meters is one of the largest in Ibaraki Prefecture. The posterior circular portion is 65 meters in diameter and numerous haniwa have been recovered.
Likewise, the Kurumazuka Kofun, with a diameter of 88 meters is one of the largest circular-type kofun in Japan. From they grave goods and construction techniques, it is estimated that these tumuli were built from the mid-3rd century to late 4th century.
The surrounding Higekama Ipponmatsu site is a large-scale settlement trace that had continued from the Yayoi period into the Kofun period, so it can be assumed that this necropolis is for the local kings of this region. Its location overlooking the ocean and the mouth of the Naka River also hints at the possibility that these local kings had some maritime connection to the Yamato region of western Japan. The Ōarai Isozaki Shrine is a Shinto shrine located nearby and is dedicated to the Nakakunizo clan, which may also have a connection to these tumuli.
The site is a 12-minute walk from Ōarai Station.
Name | Location | Type | Size | Date | Status | |
---|---|---|---|---|---|---|
1 | Himezuka Kofun 姫塚古墳 | 36°19′4.55″N140°34′15.95″E / 36.3179306°N 140.5710972°E | co-joined rectangles | 29 m length | mid-3rd C | National H.S. |
2 | Gohonmatsu Kofun 五本松古墳 | 36°19′3.6″N140°34′10.8″E / 36.317667°N 140.569667°E | indeterminate | - | late-3rd to early 4th | |
3 | Gohonmatsushita Kofun 五本松下古墳 | 36°19′4.8″N140°34′12.9″E / 36.318000°N 140.570250°E | indeterminate | - | late-3rd to early 4th | |
4 | Bochiyama Kofun 坊主山古墳 | 36°19′1.57″N140°34′19.48″E / 36.3171028°N 140.5720778°E | Keyhole | 63 m length | early 4th C | |
5 | Hisagezuka Kofun 日下ヶ塚古墳 | 36°18′57.60″N140°34′13.33″E / 36.3160000°N 140.5703694°E | Keyhole | 101.4 m length | mid-4th C | National H.S. |
6 | Kurumazuka Kofun 車塚古墳 | 36°19′2.55″N140°34′34.70″E / 36.3173750°N 140.5763056°E | Dome | 88 m length | late-4th C | National H.S. |
The Rokuroseyama Kofun Cluster is a group kofun burial mounds located in the Maruoka neighborhood of the city of Sakai, Fukui in the Hokuriku region of Japan. The site was designated a National Historic Site of Japan in 1990.
The Nakagō Kofun Cluster is a group of kofun burial mounds located in the Sakashita neighborhood of the city of Tsuruga, Fukui in the Hokuriku region of Japan. The site was designated a National Historic Site of Japan in 1988.
The Sakuradani Kofun Cluster is a group of kofun burial mounds located in the Ōta neighborhood of the city of Takaoka, Toyama in the Hokuriku region of Japan. Two of the tumuli were designated as a National Historic Site of Japan in 1934.
The Shimokomatsu Kofun group is the collective name for an archaeological site consisting of six separate clusters of Kofun period burial mounds located in what is now part of the town of Kawanishi, Yamagata in the Tōhoku region of Japan. The site was designated a National Historic Site of Japan in 2000.
Sengenyama Kofun (浅間山古墳) is a Kofun period burial mound located in the Kuraganomachi neighborhood the city of Takasaki, Gunma Prefecture in the northern Kantō region of Japan. It was designated a National Historic Site of Japan in 1927. It is the second largest kofun in Gunma Prefecture after the Ōta Tenjinyama Kofun (Ōta), and third in the Kantō region after the Ōta Tenjinyama Kofun and the Funazukayama Kofun. It is estimated to have been built around the end of the 4th century and the beginning of the 5th century and is part of a group of 13 tumuli which were concentrated in the vicinity, forming the Kuragano kofun cluster.
The Nomi Kofun Cluster (能美古墳群) consists of five groups of kofun burial mounds in Terai, Ishikawa in the Hokuriku region of Japan. Two of these kofun clusters were collectively designated a National Historic Site of Japan in 1975, with the Akitsuneyama Kofun Cluster added in 1998 and expanded in 2000, and the Teraiyama and Nishiyama clusters added in 2013.
Funakiyama Kofun group is a cluster of Kofun period burial mounds located the city of Motosu, Gifu Prefecture in the Chūbu region of Japan. It was designated a National Historic Site of Japan in 2018.
The Atagoyama Kofun (愛宕山古墳) is a kofun burial mound located in the Atago neighborhood of the city of Mito in Ibaraki Prefecture in the northern Kantō region of Japan. It received protection as a National Historic Site in 1934.
The Kawarazuka Kofun (瓦塚古墳) is a kofun burial mound located in the city of Gyōda, Saitama Prefecture, in the Kantō region of Japan. The tumulus was designated a National Historic Site in 1938 and re-designated as a Special National Historic Site of Japan in 2020 as part of the Sakitama Kofun Cluster.
The Nakanoyama Kofun (中の山古墳) is a kofun burial mound located in the city of Gyōda, Saitama Prefecture, in the Kantō region of Japan. The tumulus was designated a National Historic Site in 1938 and re-designated as a Special National Historic Site of Japan in 2020 as part of the Sakitama Kofun Cluster.
The Atagoyama Kofun (愛宕山古墳) is a kofun burial mound located in the city of Gyōda, Saitama Prefecture, in the Kantō region of Japan. The tumulus was designated a National Historic Site in 1938 and re-designated as a Special National Historic Site of Japan in 2020 as part of the Sakitama Kofun Cluster.
The Mihata Kofun Cluster (美旗古墳群) is a group of Kofun period burial mounds located in the Mihata neighborhood of the city of Nabari, Mie in the Kansai region of Japan. It was designated a National Historic Site of Japan in 1978. It is the largest group of kofun in the Iga region.
The Kasugayama Kofun Cluster (春日山古墳群) is a group of Kofun to early Nara period burial mound located between the Manotaniguchi neighborhood of the city of Ōtsu, Shiga in the Kansai region of Japan. A portion of this tumuli cluster was designated a National Historic Site of Japan in 1974.
The Chausuyama Kofun (茶臼山古墳) is a Kofun period burial mound located in the Akibadai neighborhood of Ōtsu, Shiga in the Kansai region of Japan. The tumulus was designated a National Historic Site of Japan in 1921. With a total length of 122 meters, it is the third largest kofun in Shiga Prefecture.
The Kohori Kofun Cluster (古保利古墳群) is a group of Kofun to early Nara period burial mound located in the Takatsuki neighborhood of the city of Nagahama, Shiga Prefecture in the Kansai region of Japan. It was designated a National Historic Site of Japan in 2003. It is the largest kofun cluster in Shiga Prefecture.
The Iwaseoyama Kofun Cluster is a group of Kofun period burial mounds located on the Iwaseo mountains spreading across the Mineyama, Muromachi, Miyawaki, Nishikasuga, Tsuruichi, and Nishitakara neighborhoods of the city of Takamatsu, Kagawa Prefecture on the island of Shikoku Japan. The cluster was designated a National Historic Site in 1934, with the era under protection expanded in 1985 and 1989..
The Hashizu Kofun Cluster (橋津古墳群) is a group of Kofun period burial mounds located in the Hashizu neighborhood of the town of Yurihama, Tottori Prefecture in the San'in region of Japan. The tumulus group was designated a National Historic Site of Japan in 1957.
The Miwayama Kofun cluster is a group of kofun burial mounds located in Ninomiya neighborhood of the city of Tsuyama, Okayama Prefecture, in the San'yō region of Japan. The tumuli were collectively designated a National Historic Site in 2015.
The Ōmoto Kofun Cluster is a group of Kofun period burial mounds located on the Toda-chō neighborhood of the city of Masuda, Shimane Prefecture in the San'in region of Japan. The cluster was designated a National Historic Site in 2020.
Kawaminami Kofun Cluster (川南古墳群) is a group Kofun period burial mounds, located in the Nishibeppu neighborhood of the town of Kawaminami, Miyazaki on the island of Kyushu Japan. The tumulus cluster was collectively designated a National Historic Site of Japan in 1961.