Timok

Timok (Cyrillic: Тимок) is a river in Serbia. It takes its source from the western parts of Stara Planina) and is a border river between the republics of Serbia and Montenegro and Bulgaria for 15 km. Timok is a right tributary of the Danube. The river's mouth is the northwesternmost point of Bulgaria. Timok's length is 189 km. The river's average discharge is 40 m³/s and its watershed embraces 4666 km².

The river has been greatly ecologically damaged in recent years by the Serbian mining and heavy metal industry in Bor and Krivelj and is consequently polluting the Danube with lead, copper and cadmium.

The towns of Knjaževac and Zaječar in Serbia and Montenegro and Bregovo in Bulgaria are situated on the river.