Researchers in Japan have established that a pile of stones found 3 years ago is a burial mound, probably the grave of an emperor.

The mound dates to the mid-17th century and it is square. At the site it was found archaeologists had discovered a section of outer moat with boulders lined along one of its slopes. The site is quite large with only a small portion of it excavated, and the mound itself is estimated to initially have measured 70 metres on each side. This has led researchers to the assumption that it was almost certainly an emperor who was buried there. Researchers speculate that the emperor was Jomei, father to two more famous emperors, Tenji and Tenmu, or Soga no Emishi, another significant figure.

The excavation took place in an area 65 metres south of the moat. They have not uncovered the entire mound yet, but the distance between the remains of the side walls of the passage, leading to the underground stone chamber, and the area where the stones were removed from to build the structure indicates that the passage was 2.6 metres wide.

The announcement of the discovery was made by researchers at the Archaeological Institute of Kashihara, at the Nara Prefecture on March 1.