During this period, the Kantō region was inhabited by the Jōmon people, many of whom lived in coastal settlements.

The middens associated with such settlements contain bone, botanical material, mollusc shells, sherds, lithics, and other artifacts and ecofacts associated with the now-vanished inhabitants, and these features, provide a useful source into the diets and habits of Jōmon society.

The Kamitakatsu Shell Midden is located on the edge of the hill on the right bank of the Sakura River, which flows into the innermost part of Nishiura in Lake Kasumigaura, on the western outskirts of Tsuchiura City.

By measuring the growth ring of the shells, it was found that about 70% of the shells were collected intensively from early spring to early summer, leading to the hypothesis that a large number were processed as dried seafood, either for storage or as a trade good for inland settlements.

[2] The site is open to the public as the Kamikotsu Kaizuka Hometown History Plaza (上高津貝塚ふるさと歴史の広場, Kamitakatsu Kaizuka furusato rekishi no hiroba) with a museum and reconstructions of pit dwellings.