Kasori Shell Mound

The Kasori Shell Mounds is an archaeological site in the Sakuragi neighborhood of Wakaba ward of the city of Chiba, Chiba Prefecture, in the Kantō region of Japan. It contains the largest known shell midden found in Japan, and was designated a National Historic Site of Japan in 1971. Its status was raised to that of a special National Historic Site in 2017

Source: Wikipedia