In the period from 538-710 the Japanese capital was at Asuka, 25km south of Nara. At the time there was no permanent residence of the emperors. With every succession a new palace was built and the court moved. This was due to the believe that the predecessor's spirit remained in the old site.
As a consequence, the area is dotted with ruins and burial mounds. In the Takamatsuzuka area (closest to Asuka station) there is a mural museum showing replicas of how it looks inside a burial mound. Please check the official website for more information.
OUV
The burial mounds are similar to those found in Korea. But this being Japanese, the site being relatively large and the time period not well covered in the current Japanese list, I feel this should be inscribed. Unfortunately, I did not make it to the other Japanese burial mound item on the tentative list, Mozu-Furuichi Kofungun, so I cannot compare the two.
Getting There and Away
The site is easily accessible on the Kintetsu railway line between Nara and Yoshino (Kii Mountains). I combined Yoshino and Asuka on a day trip from Nara. Note that this is not covered by the Japan Rail Pass.