Kurumazuka Kofun (Mibu)

The Kurumazuka Kofun is located on a river terrace on the left bank of the Kurokawa River, to the northeast of the town center of Mibu Town. It is part of a group of tumuli which include the nearby Ushizuka Kofun and Atagozuka Kofun, which have different shapes, and which have separate National Historic Site designations. The Ushizuka Kofun is adjacent to the western side, while the Atagozuka Kofun is located 500 meters to the south.

The tumulus has a diameter of 82 meters and a height of 8 meters, with a flat surface on the top of the dome. It was constructed in three tiers, with the diameter of 82 meters at the bottom, 52 meters at the middle tier and 32 meters at the upper tier. It was once covered in fukiishi, and archaeological surveys have confirmed that it was once surrounded by an outer dike and two rings of moats with a width of 7.5 meters. The tomb was pillaged in ancient times, leaving only the well-preserved stone burial chamber made from blocks of tuff, which has been open to the elements since at least the Edo period. The burial chamber has dimensions of 3 meters long by 2.8 meters wide by 2.3 meters in height with a 1.35 meter high entrance.

No haniwa have been recovered from the vicinity, and the lack of grave goods complicates dating, but the tumulus is estimated to date from the early 7th century. This was a period of transition between the Kofun period and the Asuka period when the Shimotsuke area was ruled by semi-independent local kings and the centralized Yamato state. Its size, and location near other large tumuli and the site of the Shimotsuke Kokubun-ji indicate the importance of this region in Kofun period Shimotsuke.

The Kurumazuka Kofun is about a 20-minute walk from Mibu Station on the Tōbu Railway Utsunomiya Line.

• List of Historic Sites of Japan (Tochigi)

Media related to Mibu-Kurumazuka Kofun at Wikimedia Commons

• Tochigi Tourist Information (in Japanese)
• Mibu Department of Education