[1] The shōen or medieval landed estates in Japan, were private, tax-free, and autonomous feudal manors which arose with the decline of the ritsuryō system.

The earliest shōen developed in the Nara period to encourage land reclamation and provided for the succession of the right to cultivate reclaimed fields in perpetuity.

The Jōbenoma Site is located at the eastern end of Toyama Bay on the right bank of the delta of the Kurobe River, on the coastline of the Sea of Japan.

A stream with a width of 30 meters once flowed from the south to the north through the site, with the building complex surrounded by walls on the west bank.

The discovery of shards of Chinese blue and white celadon porcelain found at the site, leads to the conclusion that this shōen was part of the estates held by either the temple of Tōdai-ji or of Saidai-ji in Nara.