After flowing south from Mount Ōkawairi, the river enters Gifu Prefecture and forms theprefectural border with Aichi Prefecture between the cities ofEna andToyota. Downstream, theYahagifuru River (矢作古川Yahagifuru-kawa) follows the original path of the river; however, the river was changed to its current path at the beginning of theEdo period because of flooding. The river forms the border between the cities ofNishio andHekinan when it flows into Mikawa Bay.
