and Honshu. On the other hand, wealthy zempo-koen fun (keyhole kofun) during this period were approximately 5000 from the middle of the 3rd century in the Yayoi period to the 7th century in the Asuka period in the Japanese archipelago, and many of them were massive.

In comparison, in the southern Korean peninsula, there were only 13 from the 5th century to the 6th century, and the tombs were small. Wall decorations and Japanese-style armour characteristic of kofun