Nishi-Umazuka Tomb (Nishi-Umazuka Kofun)
The Nishi-Umazuka tomb is a square burial mound surrounded by homes. It is managed by the Imperial Household Agency, which reports that it is a subsidiary tomb of the tomb of Emperor Ōjin. However, it is much closer to the Hakayama Tomb, and some scholars believe that it is connected to that site.
The name Nishi-Umazuka (“West Horse Tomb”) comes from the speculation that the tomb was built for Emperor Ōjin’s horses. Based on its size, some experts think that is not actually the case. Since the Imperial Household Agency keeps the tomb sealed out of respect, it is not possible to open the burial chamber and investigate.
It appears that some of the mound’s original footprint has been covered over by modern construction. Excavations around the edges suggest that the original mound was 9.4 meters high and covered an area of about 0.2 hectares.