 the struma or strymÃ³nas (bulgarian Ð¡ÑÑÑÐ¼Ð°, pronounced , greek Î£ÏÏÏÎ¼ÏÎ½Î±Ï , turkish (struma) karasu 'black water') is a river in bulgaria and greece. its ancient name was strymÅn (greek: Î£ÏÏÏÎ¼ÏÎ½ ). its catchment area is 10,800&nbsp;kmÂ². it takes its source from the vitosha mountain in bulgaria, runs first westward, then southward, 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&nbsp;km (of which 290&nbsp;km in bulgaria, making it the country's fifth longest). parts of the river valley belong to a bulgarian coal-producing area, more significant in the past than nowadays. the greek portion is a valley which is dominant in agriculture, being greece's fourth biggest valley. the tributaries include the rila river, the dragovishtitsa, the blagoevgradska bistritsa, the konska river, the sandanska bistritsa and the angitis. ==history== left|thumb|250px|the basin of the river in bulgaria the ancient greek city of amphipolis was founded near the river's entrance to the aegean, at the site previously known as ennea odoi (nine roads). when xerxes i of persia crossed the river during his invasion in 480 bc he buried alive nine young boys and nine maidens as a sacrifice to the river god.herodotus 7,114 . the history may be greek slander, though, as human sacrifice is not known as an iranian cultic practice. the forces of alexander i of macedon defeated the remnants of xerxes' army near ennea odoi in 479 bc. in 424 bc the spartan general brasidas after crossing the entire greek peninsula sieged and conquered amphipolis. the battle of kleidion was fought by the river in 1014. in 1913, the greek army was nearly surrounded in the kresna gorge of the struma during the [[second 
Geography_of_Kyustendil_Province Geography_of_Pernik_Province International_rivers_of_Europe Rivers_of_Bulgaria Rivers_of_Greece