BioEd Online

Japan's royal tombs are to be opened to more thorough investigation by researchers for the first time. The move should re-invigorate studies into the country's ancient history, which have so far depended mostly on legends and myths.

But the change in the rules still won't allow any excavation, nor the inspection of any bodies. It won't, therefore, solve the big mysteries such as which emperor lies in which tomb, or whether the imperial family has remained purely Japanese or, as some have claimed, been influenced by Korean and Chinese bloodlines.

The Imperial Household Agency, which tightly controls the privacy of the royal family, made the decision in late December. The move follows a 2005 petition from 15 academic associations, including archaeologists, zoologists and botanists, to open up 11 royal tombs.

Peace and quiet

Japan has hundreds of royal tombs, but the agency has prohibited the public from entering them to protect "the imperial ancestors' serene silence and security".

Most of the tombs are shaped like a massive keyhole, with the outline formed by earthen mounds and moats. They are thought to be graves of emperors who reined between the 4th and the 6th centuries, when large tombs were a symbol of power.

The imperial agency has had its own researchers examine the tombs. But academic archaeologists have only been allowed to explore the outmost bank of a given site, and even that only when the agency is doing repair work with its own researchers or during other special occasions. Investigators could not choose which tomb to visit, nor could they linger and take detailed observations.

Under the new rules, one researcher per association will be allowed to climb the outer mound of a given tomb and observe whatever features are visible from there in detail. The agency has yet to decide how many tombs it will open.

Seen first hand

"It will be a big step forward" for Japanese archaeology, says Tetsuo Hishida, at Kyoto Prefectural University.

One tomb that researchers are keen to get their hands on is that of Japan's 16th emperor, Nintoku, who lived in the 4th or 5th century. At 486 metres long, it is reputed to be the biggest in the world. "The tomb of Nintoku is described in school textbooks, but no researchers [outside the Imperial Agency] have seen it. That's a shame," Hishida says.

Hishida and other archaeologists are keen to examine more closely the quality and design of stones and ritual clay figures called 'haniwa' found around the outer mound. From such observations they hope to date the tombs more accurately, and learn more about the lifestyle of those alive at the time, says Fumiaki Imao, a researcher at the archaeological research institute of Kashihara, Nara Prefecture, Japan's ancient capital.

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