In Fujiwarakyo capital, Heijokyo capital, and Heiankyo capital which introduced a Chinese city plan, and promoted as a place for common folk, were of earthfast architecture, therefore the wetlands and shores of rivers prone to flooding were abandoned due to their being unfit for living, changing the location of the cities from the original plans.
中国風の都市計画を持ち込んだ藤原京・平城京・平安京などでは、計画的な庶民の居住を促しても、家が掘立柱建築だったために、地下水位の高い低湿地や河川の氾濫原は居住に適さないとして放棄され、いずれも当初の計画とは異なる都市へと変化した。