Negoyadai Site, Archaeological site in Utsunomiya, Japan.

The Negoyadai Site occupies the right fluvial terrace of the Sugatagawa River in the Kamikake neighborhood of Utsunomiya. Excavations from 1982 to 1988 uncovered pit dwellings, square pillar buildings, raised-floor structures and more than 339 grave pits arranged around a central plaza. Four pit dwellings have been reconstructed in the park.

Excavations between 1982 and 1988 revealed remains from the Jomon period, one of Japan's earliest cultural periods. The findings show how settlements and burial practices developed during this ancient era.

The cemetery displays clusters of five to ten graves arranged around a central plaza. This layout gives a sense of how ancient communities organized their burial practices.

The site lies in the Kamikake neighborhood of Utsunomiya, on the right terrace of the Sugatagawa River, about 30 minutes by car from Utsunomiya Station on the Tōhoku Shinkansen. The grounds are laid out as the Utsunomiya Archaeological Park, with four reconstructed pit dwellings around the former cemetery area.

The excavated raised-floor structures reach up to 24 meters in length and suggest advanced building skills. Such large rectangular buildings are uncommon for this early period and raise questions about how Jomon communities were organized.