EncyclopediaIskŭr
Iskŭr (is'ker) [key], river, c.250 mi (400 km) long, rising in the Rhodope Mts., W Bulgaria, and flowing generally NE past Sofia and through the Balkan Mts. to the Danube River. The gorge of the Iskŭr is one of the chief passes through the Balkans.
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