Miyazuka Tumulus (宮塚古墳 (埼玉県))
Miyazuka Tumulus is located at Hirose 608, Kumagaya City, Saitama Prefecture, which has a unique two-stepped form with a rectangular-shaped lower layer and a circular-shaped upper layer.
Miyazuka Tumulus is one of the tombs among Hirose Tumulus Group consisting of many small-scale tumulus, and it is considered this tumulus was constructed in late 7th century. This tumulus is constructed in a unique style, combining a rectilinear soil embankment in 17m (east side) by 24m (west side) with the height of 4.1m, and a circular shaped upper volume with the diameter in 10m with the height of 2.5m. It is a rare case in Kanto region that this unique two-stepped tumulus with a circular upper and a rectangular bottom has preserved its original form. However, some study suggests that this tumulus was originally in a simple shape in either circular or rectangular volume, and in later years the volume of the tumulus was carved out when farmers used the surface ground of the tumulus for agricultural purpose. Some of the surfacing stones have also remained until today. This tumulus is also known as 'Sannozuka' as it is located in the area called "Sanno" (mountain king) with a level ground. It also has a nickname known as 'Osonaezuka' (offering mound).
The designation as a historical place
On May 15, 1956, this tumulus was designated as a national historical place.