Iskar River

Iskar (Искър)
Map of the Iskar
Country	Bulgaria
Basin
Main source	under Damga Peak, Rila, Bulgaria 2,500 m (8,200 ft) 42°11′40″N 23°19′50″E / 42.19444°N 23.33056°E / 42.19444; 23.33056
River mouth	north of Gigen, Pleven Province
Basin size	8,646 km2 (3,338 sq mi)
Physical characteristics
Length	368 km (229 mi)

The Iskar (Bulgarian: Искър pronounced [ˈiskɐr]; Latin: Oescus; Ancient Greek: Οἶσκος) is, with a length of 368 km, the longest river that runs solely in Bulgaria, and a tributary of the Danube.

The Iskar is formed by three rivers, the Chèrni (black) Iskar, Bèli (white) Iskar and Lèvi (left) Iskar (known under the collective name Ìskrove), with the source being accepted to be the Prav (straight) Iskar, a tributary of the Cherni Iskar. After descending from the north slopes of Rila, it fills the Iskar Reservoir—the largest in Bulgaria and the Lake Pancharevo. The river runs through the outskirts of Sofia and passes through a rocky gorge in the Balkan Mountains. It flows into the Danube near the village of Gigen in Pleven Province. The Iskar is the only river to take its source from southern Bulgaria and cross the Balkan Mountains to flow into the Danube.

The Iskar flows through seven provinces of Bulgaria: the capital city of Sofia, Sofia Province, Pernik Province, Vratsa Province, Pleven Province and Lovech Province. This is the main source of water for Sofiyskavoda, the water and sewarage company in Sofia.

In terms of geology, the Iskar is the oldest river in the Balkans and also the only one to have preserved its original direction despite the significant geological changes in later stages.