The country is dotted with kofun that are considered to share the blueprint of the burial mound, which is so big as to be mistaken as a naturally formed knoll, having a total length of about 280 meters and a height of approximately 30 meters at the rounded rear.
墳丘の全長約280m、後円部の高さ約30mで自然にできた小山と錯覚するほどの規模、全国各地に墳丘の設計図を共有していると考えられる古墳が点在している点。