Some 1,500 people took part Sunday in an event in Takatsuki, Osaka Prefecture, to pull a stone burial chamber on a wooden sled to re-enact how the ancients might have buried those of high rank.

The participants took turns pulling the stone coffin weighing some 7 tons. It had been brought from Kumamoto Prefecture aboard a replica of the sailing vessels that were used in ancient times.

The event was part of a project delving into the mystery of why many ancient burial mounds in the Kansai region have coffins made of stone that can be traced back to Kyushu.

The Imashirozuka burial mound, believed to date from the first half of the sixth century, is located in Takatsuki.

The vessel that carried the chamber for the project was propelled by oars and took 34 days to navigate from the Ariake Sea to Osaka Bay.