Somanouchi-kofun Tumulus Cluster (a tumulus cluster in Tenri City, Nara Prefecture) (杣之内古墳群)

Somanouchi-kofun Tumulus Cluster is a tumulus cluster in Tenri City, Nara Prefecture. The mounds are distributed in south of Isonokami-jingu Shrine along the load neighborhood of a mountain.

Summary

The tumulus cluster dot Somanouchi-cho, Magata-cho, and Otogi-cho in Tenri City. They are located in the south of the Furu-kawa River and constructed using the hill extending from east. There is Ishikami Toyota-kofun Tumulus Cluster on the north across the Furu Site, and Kayo-kofun Tumulus Cluster, which is the north branch group of Oyamato-kofun Tumulus Cluster, is on the south across the Furu Site. The burial mounds are characterized by the change in the shape of mounds from the keyhole-shaped to the round barrow through the huge round barrow. Regarding the buried people, it is thought to have a relation to the Mononobe clan.

Major tumuli

Nishiyama Tumulus: Constructed in the early Kofun period (tumulus period). The 183-meter-long tumulus is the largest square front, square back mound in Japan.

Kohanbozuka Tumulus: A keyhole-shaped mound which was located on about 200 meters north of Nishiyama-kofun Tumulus. It had a total length of 92 meters, and includes the back circular part of 52 meters in diameter, and the front square part facing west. Similar to Nishiyama-kofun Tumulus, it was constructed in the early Kofun period, but has been lost during World War II.

Obaka-kofun Tumulus: A keyhole-shaped mound, which has the front square part facing southwest, and was constructed in the middle of Kofun period. It is about 80 meters long and 6 meters high at present, however, the original height is unknown since the top of the tumulus was leveled. During the excavation research in 1978, a wooden haniwa (figure artifact) was excavated from the surrounding moats.

Kasakamiyama-kofun Tumulus: A 45-meter-long keyhole-shaped mound whose front square part facing northwest. Middle of Kofun period.

Nishinorikura-kofun Tumulus: A keyhole-shaped mound, which is thought that was constructed in the late Kofun period (the early sixth century.)
It has the total length of 120 meters and the height of 18 meters, and includes the front square part facing the south. The tumulus is surrounded with empty moats in about 20 meters depth, which is seen as the outer moat, was confirmed on the south side of the front square part by the results of the research.

Higashinorikura-kofun Tumulus: A keyhole-shaped mound, which is thought that was constructed in the late Kofun period (the mid-sixth century). It has the total length of 75 meters and the height of 10 meters, and the front square part faces the west. It has the 14.6-meter-long horizontal stone chamber open to the south.

Tsukaanayama-kofun Tumulus: A round barrow of 64 meters in diameter, which is located on the north of Nishiyama-kofun Tumulus and constructed in the end of Kofun period. Although the ceiling stone has been lost, it has the 17-meters-long stone chamber. The way to place the gigantic stones of equal size on the passage part is in common with Ishibutai-kofun Tumulus.

Minezuka-kofun Tumulus: A round barrow of 35 meters in diameter and 6 meters in height, which has the two stage construction and is located about 500 meters east of Nishiyama-kofun Tumulus. The tumulus is also called Hakayama (i.e. grave mound), since it is located under the cemetery. It was constructed in the end of Kofun period (from the end of sixth century to the early seventh century) and has been known of the horizontal stone chamber using beautifully arranged gigantic stones, which is called Iwayayama-kofun Tumulus. Fukiishi (a stone covering an old tomb) using kiriishi (cut stones) is provided for the tumulus.

Hoshozuka-kofun Tumulus: A round barrow of about 17 meters in diameter at present. It has been severely leveled and the original shape and size are unknown. However, there is a research result showing that the tumulus was the round barrow of 25 to 35 meters in diameter.