Nishiyamazuka Tumulus (西山塚古墳)
The Nishiyamazuka tumulus is a keyhole-shaped one located in Tenri City, Nara Prefecture.
Summary
With a total length of 114m, its front part is 70m in width and 8m in height, and the round part is 13m in height and 65m in diameter. With cylindrical haniwa (unglazed terra-cotta cylinders and hollow sculptures arranged on and around the mounded tombs [kofun]) having been unearthed, it is presumed, based on their shapes, that this tumulus might have been constructed in the latter half of the fifth century, being exceptional for tumuli in this area.
There is a theory that the Fusumada no haka, where according to Engishiki (codes and procedures on national rites and prayers), Princess Tashiraka, the wife of Emperor Keitai, was buried, is not the Nishitonotsuka Tumulus but this tumulus.
As an evidence for the theory, it is said that the haniwa there were baked in the Shinike remains as those in the Imashirozuka tumulus, said to be the true tumulus of Emperor Keitai