In the main part of the burial facilities on the rounded rear part of the tumulus, there is an estimated 9.4-meter long, large-scale Nendokaku (clay surrounding wooden coffin), of which the main part had been robbed.
後円部の埋葬施設の主体部は、憤丘主軸に平行する木棺を覆った粘土槨があり、長さ推定9.4メートルの及ぶ大規模なもので、主要部分は盗掘を受けていた。