Struma

The Struma or Strymónas Karasu [kaɾaˈsu], 'black water') is a river in Bulgaria and Greece. Its ancient name was Strymṓn . Its drainage area is 17,330 km2 , of which 8,670 km2 in Bulgaria, 6,295 km2 in Greece and the remaining 2,365 km2 in North Macedonia and Serbia. It takes its source from the Vitosha Mountain in Bulgaria, runs first westward, then southward, forming a number of gorges, enters Greek territory at the Kula village. In Greece it is the main waterway feeding and exiting from Lake Kerkini, a significant centre for migratory wildfowl. The river flows into the Strymonian Gulf in Aegean Sea, near Amphipolis in the Serres regional unit. The river's length is 415 kilometres in Bulgaria, making it the country's fifth-longest and one of the longest rivers that run solely in the interior of the Balkans.

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