Melen (tur. Melen Çayı) is a river in northern Turkey in the Duzce silt, flowing into the Black Sea, located between Istanbul and Ankara.
It is the main source of drinking water for Istanbul.
Melun is the generalized name of two rivers separated by a lake. From the source to the lake, this river is called “Kyuchuk-Melen”, and from the lake to the Black Sea, this river is called “Buyuk-Melen”. The lake, which is a transshipment link in the life of the river, is also called Melun.