An artist rendering of how the burial mound of Asuka originally looked

Moat ruins found in Japan may be part of a burial mound for an ancient emperor

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Archaeologists in Japan have unearthed a huge stone-paved moat in Asuka, Nara Prefecture, which they believe is part of a burial mound for an ancient emperor.  The finding adds to a string of fascinating discoveries in the small village of Asuka, from pyramid-like structures to multiple carved granite stones in peculiar shapes dotted across the region.

According to The Asashi Shimbun , the remnants of the moat, which were found at the archaeological site of Koyamada, measure 48 meters (158ft) in length and 3.9 (13ft) to 7 meters (23ft) in width. The moat is lined with 40-centimeter quartz diorite boulders along its northern slope, while the southern slope is covered with flagstones stacked in a staircase pattern, and the bottom is covered with smaller rocks.

The moat in Asuka, Nara Prefecture, that is believed to be part of the first burial site of Emperor Jomei.

The moat in Asuka, Nara Prefecture, that is believed to be part of the first burial site of Emperor Jomei. Credit: Asahi Shimbun.

The research team believes that the moat forms the outer perimeter of a square-shaped tumulus, or burial mound, with each side measuring 50 meters (164ft) to 80 meters (262ft). The Japan News reports that this would make it the “biggest rectangular ancient tomb in the Asuka district at that time,” even larger in size that the renowned Ishibutai grave in Asuka, which measures 50 by 50 meters. The Ishibutai Kofun is the largest known megalithic structure in Japan and is believed to be the grave of Umako, powerful leader of the Soga clan of Japan.

The Ishibutai Kofun, believed to be the tomb of Umako.

The Ishibutai Kofun, believed to be the tomb of Umako. ( Wikipedia)

The ruins have been preliminarily dated to the mid-seventh century, and based on its location, size, age, and unique construction method, archaeologists believe the tumulus is a tomb for an ancient emperor.

“The mound is highly likely the first burial site of Emperor Jomei (593-641), described in the ‘Nihon Shoki’ (The Chronicles of Japan) as the place where his body rested until it was later transferred to another location,” Fuminori Sugaya, the director of the Archaeological Institute of Kashihara, told the Asashi Shimbun.

According to Princeton, Emperor Jomei was the 34 th emperor of Japan, according to the traditional order of succession, and he reigned for 13 years. Until now, the emperor has been venerated at a memorial Shinto shrine at the Dannozuka burial mound in Sakurai, Nara Prefecture, and the Imperial Household Agency designates this location as Jomei’s mausoleum, but this may have to change if researchers confirm the newly discovered burial mound belonged to Emperor Jomei.  The Dannozuka burial mound was built according to the same design and with the same materials.

Nevertheless, The Japan Times reports that some experts do not believe the newly discovered burial mound belonged to Jomei, and instead may have been the grave of Emishi (unknown – 645 AD), a statesman of the Yamato Imperial Court and son of Umako.

The discovery of the moat follows another incredible finding in the village of Asuka. Late last year, archaeologists found that a large mound contained a pyramid-shaped tomb underneath dated to the latter half of the sixth century. Researchers uncovered stepped layers made of stone, which had been hidden over the years by the grassy mound.  

Artist’s rendition of the Miyakozuka pyramid-shaped tomb.

Artist’s rendition of the Miyakozuka pyramid-shaped tomb. Credit: Yomiuri Shimbun

The village of Asuka is known to be an ancient land with historical interest. It has its origins in the Tumulus Period (250-552 AD), also called Kofun jidai, which means Old Mound period.  This era of Japanese history is characterized by a particular type of burial mound that was popular at the time; specifically key shaped earthen mounds surrounded by moats.

The village is also known for its many megalithic structures. The largest and most enigmatic of the carved stones in Asuka is the Masuda-no-iwafune (the 'Rock Ship of Masuda' ). Very little is known about the Masuda no iwafune stone carving, as well as other megalithic structures and constructions in the region of Asuka.

Featured image: An artist rendering of how the burial mound originally looked (Provided by the Archaeological Institute of Kashihara)

By April Holloway


Roberto Peron's picture

Amazing isn't it?  Pyramids all over the world!  And yet we are to believe ancient peoples had little or no contact especially across oceans?  I don't think human history as we have been TOLD is fully correct.


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