The Boyuk Chay River (In Persian: بویوک چای) is a river in northwest Iran.[1][2]
The river is at 37°58'0"N and 47°45'0"E between Sarab and Ardabil, near Kalian, has an elevation of 1475meters[3] and flows into Lake Urmia via Aji Chay River.
The area has a cold semi-arid (climate).