When investigating the possible location of Heijo-kyo, Sadamasa KITAURA discovered that ruins of the city remained on the ridges between rice fields and streets, which he recorded in "Heijo-kyu Daidairi ato tsubowari no zu," in 1852.
北浦定政が、自力で平城京の推定地を調査し、水田の畦や道路に街の痕跡が残ることを見つけ、1852年（嘉永5）『平城宮大内裏跡坪割之図』にまとめた。