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ancient burial mound; barrow; tumulus
古墳を上から見ると鍵穴の形だ。
Seen from above, the tomb is keyhole-shaped.
この古墳は四世紀に造られた。
This ancient tomb was built in the 4th century.
古墳から多くの副葬品が出土した。
Many burial goods were unearthed from the tomb.