The Imperial Household Agency and the Sakai municipal government in October launched a joint excavation project on a huge “kofun” ancient burial mound in the city.

The Daisen kofun, identified by some ancient documents as the grave of Emperor Nintoku (first half of the fifth century), features one of the largest keyhole-shaped mounds in Japan.

The site, also known as “Nintoku Tenno Ryo” (the mausoleum of Emperor Nintoku), and believed to be a burial place for emperors, empresses and other members of the imperial family, has been protected and preserved by the Imperial Household Agency as an imperial property.

It was designated as the Nintoku Mausoleum in the late 19th century according to descriptions in such ancient documents as “Kojiki” (Records of Ancient Matters) and “Nihonshoki” (Chronicles of Japan) in the eighth century and “Engishiki,” a collection of governmental rules and formalities, compiled in the 10th century.

Archeological studies and findings from excavations in recent years have shown, however, that the years when many imperial mausoleums were built are not consistent with the eras of the emperors and other royalties who the agency says lie buried within them.

There are various theories about the actual tomb owner of the Daisen kofun.

The agency remains reluctant to permit a full-scale academic investigation of the gigantic kofun, citing the need to maintain “tranquility and dignity.”

The central mound, which houses the burial facilities, will not be covered by the joint excavation project, which the agency says will be limited in scale.

But there are doubts and concerns among archeologists and historians about allowing the kofun to be formally described as an imperial mausoleum while the identities of the buried individuals have not been academically confirmed.

The agency should change its stance and allow large-scale academic research to uncover facts about the situation surrounding the construction of the kofun including the identities of the buried people so that reliable and confirmed information about this historical site can be provided internationally.

In 2008, the agency allowed a small group of leading researchers to enter the burial mound for inspections. But it has adamantly refused to open the site to the public.

It says the joint excavation project is aimed only at gathering basic information for its plan to conduct revetment work on the mound and embankments as part of the conservation efforts for the entire site. The excavation work will be limited to certain parts of the embankment around the moat. There is no plan to allow citizens to inspect the site as part of the project.

The government has decided to make a bid this year to secure UNESCO World Heritage status for a group of kofun in southern parts of Osaka Prefecture, known as “Mozu-Furuichi” kofungun (clusters of kofun tombs). It has nominated the group of some four dozen ancient burial sites for the distinction.

The Daisen kofun is one of the most famous and important among them, but academicians are skeptical about putting it on the UNESCO World Heritage list as “Nintoku Tenno Ryo” kofun.

Uncovering vital facts about the site clearly requires full-fledged academic research involving close examinations of the entire mound and excavations at locations in its bottom areas.

In addition to officials of the agency and the Sakai municipal government, researchers in related areas should also be allowed to join the team to study the site from a broad perspective while paying sufficient attention to its preservation.

Such huge kofun burial mounds offer valuable insights into how Japan was formed as a nation and what kind of exchanges it had with the Korean Peninsula and the Asian continent in ancient times.

To uncover the historical value of these sites for future generations, it is vital to take advantage of the latest archeological and historical knowledge in research and make the findings widely available to the public through inspection tours and exhibitions.

After the discovery of the wall paintings inside the Takamatsuzuka Kofun in Nara Prefecture in 1972, the Lower House Committee on Education made a nonpartisan call for excavations of imperial tombs for academic purposes

These kofun imperial tombs should be regarded as public cultural assets and allowed to be studied in ways that respond to people’s keen interest in Japan’s ancient history.

--The Asahi Shimbun, Nov. 9