Nōbi Plain

The Nōbi Plain (濃尾平野, Nōbi Heiya^?) is a large plain in Japan that stretches from the Mino area of southwest Gifu Prefecture to the Owari area of northwest Aichi Prefecture, covering an area of approximately 1,800 square kilometres (695 sq mi). It is an alluvial plain created by the Kiso Three Rivers (the Ibi, Kiso and Nagara rivers) and has very fertile soil. It is bordered on the west by the Ibuki and Yōrō mountain ranges, and to the east by the Owari Hills. Its northern border is marked by the Ryōhaku Mountains and the south by Ise Bay.

The downstream areas of the three areas are located in Aichi Prefecture and constitute a vast wetland, with the level of the land sometimes dipping below sea level. Because the water levels can change rapidly due to storms, there was often much water damage throughout history, leading to many distinct cultural habits, such as municipalities surrounded by earthen rings (e.g. Wanouchi, Gifu Prefecture). The modern cities of Tsushima and Nagoya in Aichi Prefecture were built on low-level plateaus to ward off water damage and flourished as a result.

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