In the old days this tomb was called the Gojyono Maruyama Kofun. Since the Meiji Period (1868-1912) it has been called by its current name, but locally it is still called Maruyama Kofun because its round back is in the Gojyono district and a large part of its front in Ogaru.
Maruyama Kofun measures 318 meters in length. The front is 15 meters long and 10 meters wide. The circular back part measures 115 meters in diameter and 21 meters in height, and the front part, 210 meters in width.
Its stone-lined crypt inside the corridor-style mound measures 28.4 meters in length, making it the longest of its kind ever discovered (most of the largest kofun have never been excavated) in the country. The dome of its roof is covered by six pieces of natural stone 4.8 meters long, 1 meter wide and 1.5 meters high. The burial chamber is 8.3 meters long and 4.1 meters wide, in which two hollow stone coffins were placed in an L-shape.
In the chamber about 1 meter high, earth and sand are piled up and, although the details of the coffins are unknown, the bottom coffin has a lid 2.42 meters long, 1.44 meters wide and 0.4 feet tall. The front coffin has a lid that is 2.75 meters long, 1.41 meters wide and 0.63 meters high. They are made of rhyolithic weld tuff (light colored volcanic igneous rock, extrusive counterpart of granite) called Tasuyama-ishi, taken from the vicinity of the Kakogawa River.
The survey of the interior of the stone chamber was carried out several times during the Edo Period (1603-1868): in 1790 by Kitaura Sadamasa, in 1796 by Tsutumi Korenori, and in 1855 by Wakisaka Awaji. With the beginning of the Meiji Period and the opening of the country to the outside world, the English mining engineer William Gowland (1842-1922), later called the "Father of Japanese Archeology", visited Japan and researched the kofun in Nara, among them theof Maruyama.
When a child from Kashihara was playing in the Maruyama Kofun with her friends in 1991, she found an entrance to the corridor-style stone chamber outside the hedge. The child's father heard the story and decided to enter the chamber with his son in the early morning of May 30th, before going to work, and took pictures of his interior.
Osaka Asahi Broadcasting Corporation, together with the Tokai University Information Center and Konica, analyzed the photographs and concluded that the front coffin was hollow and had been made in the third quarter of the 6th century, and the posterior coffin in the first quarter of the 7th century. They further determined that the granite megalith that forms the front of the stone chamber must weigh more than 100 tons, ie, larger than the 75-ton stone at Ishibutai Kofun. From its masonry pattern, they estimated that the stone chamber had been built between the end of the 6th century and the beginning of the 7th century.
Later, Mori Koichi, a professor at the time at Doshisha University, took up this story in his talk in Osaka on December 10, and TV Asahi aired thirty photos in one issue of News Station. Kofun experts endorsed the importance of these photographs. Later, from August 10th to September 15th, 1992, Kunaicho Shoryoubu (the Kunaicho Library) performed opening closing work along with an additional single measurement investigation and, after the research, published the written report.
At one time it was believed, based on local tradition, that the stone coffins were those of Temmu (631-686), the 40th Emperor of Japan (from 672), and of Jito (645-703), the 41stEmpress of Japan (from 686), the third woman to ascend the Chrysanthemum Throne, who reigned at the end of the 7th century, but this was refuted when the tomb was definitively dated to the 6th century, a century ahead of schedule.
At present, the identities of the tomb's occupants remain unknown. The most accepted theory today is that this is one of the resting places of Emperor Kinmei (509-571), the 29th Emperor of Japan (from 539), and his consort Soga no Kitashihime, parents of Empress Suiko (554-628), the 33rd Emperor of Japan (from 592). The remains of Kinmei and Kitashihime if not in Maruyama would be in Kinmei Tenno-ryo in Asuka. The Nihon Shoki (Chronicles of Japan), an ancient book of Japanese history, states that when Empress Suiko reburied her mother, she said a prayer on the road in Karu (now Ogaru, Kashihara). But the book does not give the location of the mausoleum. So what is your final resting place? The truth is buried deep in the two mausoleums.
Maruyama is not attractive at all, as seen from the ground, it appears to be no more than a huge wooded hill, even though it was entirely man-made. This is precisely because it is covered with vegetation, which prevents its true forms from being discerned, so much so that those who pass along the busy avenue in front of it do not notice anything special. Only from the top can you get a sense of its scale and keyhole-style shape. From certain angles, however, like the one in the photo I took, you can see some of its outlines.
Being one of the few kofun who is allowed to walk on him, I took the opportunity to commit this sacrilege, and while I was doing it, a middle-aged man appeared in the distance. Thinking that maybe he could provide me with additional information about kofun, I approached him and what was my surprise when he took the initiative to address me. But not to clarify, but to ask what he was doing there and what was there! I then told him that it was a kofun, and he was astonished, as he was completely unaware of it despite the fact that there was a sign indicating it. That is, if not even a Japanese citizen has the notion that the hill is artificial, it shows how much this kofun is still ignored.
And as it has never been dug deeper, I wonder what
treasures, perhaps even technological, there would not be there. The only object unearthed there – in the circular back
part – that has been released is a Chinese-style mirror that is in the
possession of Kyoto University's Department of Literature.