Nishiyama-kofun Tumulus (a tumulus in Somanouchi Town, Tenri City, Nara Prefecture) (西山古墳)

Nishiyama-kofun Tumulus is a tumulus in Somanouchi Town, Tenri City, Nara Prefecture, and designated as the national historic site.


It is thought that the tumulus was constructed in the early Kofun period (tumulus period) (the fourth century), that is to say, it was the one of the oldest in Somanouchi-kofun Tumulus Cluster that the tumulus belongs to. The tumulus is a square front, square back mound with three stage construction, whose square front facing west. The tumulus has a total length of 183 meters; the round back part is 94 meters wide and 16 meters high, and the square front part 72 meters wide. This is the largest among the square front and square back mounds in the country. The tumulus has an extremely peculiar shape, that is only the first stage of the mound has the square front and square back mound shape, on which the keyhole-shaped mound is placed, and it is believed without a doubt that the tumulus has this shape from the beginning.

The vertical stone chamber is located at the center of the square back part, but it has seemed that the chamber has been already subjected to the grave robbing. It is said that the antiaircraft artillery position was taken up by the former Japanese military during World War II, and the building stones (produced in Shibayama, Kashiwabara City) in the vertical stone chamber were dug up at that time.

Present condition

The tumulus is well preserved, and its stage construction can be clearly observed since trees are not grown.


About 20 minutes' walk from Tenri Station. About 500 meters south of Tenri University Sankokan Museum, and just north of Tenri junior high school.

[Original Japanese]