Photo/Illutration A stone coffin grave that was unearthed near the top of a hill at the ancient Yoshinogari Ruins in Saga Prefecture (Hisashi Omura)

YOSHINOGARI, Saga Prefecture--A grave with a stone coffin around 2.3 meters long and dating to the latter part of the Yayoi Period (c. 1000 B.C.-250 A.D.) was unearthed at a major archaeological site here, the prefectural government announced.

It is the largest stone coffin grave found so far at the Yoshinogari Ruins, which is designated as a site of special historic interest by the central government.

The sprawling site is located in Yoshinogari town and Kanzaki, both in Saga Prefecture.

It is believed the grave was created between the latter half of the second century and the mid-third century, when the Yamatai state existed.

Announcing the find on May 29, the prefectural government said it might be the grave of someone who was in power when the Yoshinogari settlement was at its peak.

The Yoshinogari Ruins refer to a large, moated settlement that existed from around the fifth century B.C. to the mid-third century A.D.

The site is regarded as typical of a moated settlement from the period when Yayoi culture flourished.

The stone coffin is closed and covered with four stone lids. The grave measures about 3.2 meters. It is around 1.5 times the diameter of a typical grave pit for stone coffin graves that have previously been unearthed at the site.

The coffin was buried in a hill by itself, which suggests it is the grave of an influential figure, the prefectural government said.

No grave of someone in power from the latter half of the mid-Yayoi Period to the late Yayoi Period, when the settlement significantly expanded, had been found at the Yoshinogari Ruins to date.

Numerous linear shapes are evident on the surface of two of the four stone lids.

The markings, thought to have been inscribed on the surface with sharp metal tools, strongly resemble an “x” or the Japanese katakana pronounced as “ki.”

It is said these shapes had the power to protect a buried person from evil.

The prefectural government plans to open the coffin on June 5.

“Because the coffin is this large, we might be able to find grave goods, too,” said Kinya Hosokawa, deputy director of the cultural property protection and utilization department at the prefectural government.