Andonyama Tumulus (行燈山古墳)
Andonyama Tumulus is an ancient Japanese tumulus of a circular shape rear-end with a rectangular frontage, located at Yanagimoto-cho, Tenri City, Nara Prefecture.
This tumulus was constructed at the foot of Ryuo-zan Mountain by utilizing the tip of a mountain slope, by facing its rectangular frontage side in north-west direction toward the level ground. The circular rear-end part is situated on a higher ground of a hill.
Andonyama Tumulus is the second largest tumulus next to Shibutani Mukouyama Tumulus (currently designated as the Imperial Mausoleum of Emperor Keiko) among Yamato/Yanagimoto Tumulus Group scattered around the foot of Miwa-yama Mountain, and it is now specified as the Imperial Mausoleum of Emperor Sujin (Yamanobeno Michinomagarino Okanoeno Misasagi). The political influence of Emperor Sujin is known as Miwa Court or Hatsuse Court. This is considered to be the tumulus of a great king (prior to the establishment of the Imperial Family) in early Yamato Sovereignty.
Before the restoration of the mausoleum performed at the end of Edo period, (Bunkyu era) this tumulus had been designated as the Imperial Mausoleum of Emperor Keiko, although that was thoughtlessly changed to that of Emperor Sujin's in February 1865, right before the completion of the restoration. This is a typical example that the mixed usage of the archaeological name and the Imperial name of the tumulus could cause this kind of confusion.
This tumulus is under the control of the Imperial Household Agency, thus a general public including the archaeological scholars are not allowed to enter the site without permission from the agency.
The scale and the form of the tumulus
This tumulus has 242m in its length, while its precise circular shaped rear-end in three steps has the diameter in 158m and the height in 23m. The top end of the circular rear-end part is in a flat circle. The front edge line of the rectangular frontage is slightly arced. The top edge line of this arc-end mound is slightly inclined to have a slope toward the depressed center. The ration of the dimension between the diameter of the circular rear-end and the length of the diagonal line of the rectangular frontage is about 10:8. There are bridges by the soil embankments go across the surrounding moat at the south side of the circular rear-end and the rectangular frontage, presumably existed from the beginning as the original features. The surrounding moat of the tumulus was presumably in symmetrical, shield-like shape.
There is Kushiyama Tumulus right next to this tumulus on the east side.