Adriatic Sea

Large arm of the Mediterranean Sea, lying northwest to southeast between the Italian and the Balkan peninsulas. The western shore is Italian; the eastern includes Croatia, Montenegro, and Albania, with two small strips of coastline owned by Slovenia and Bosnia Herzogovina. The Strait of Otranto, between Italy and Albania, links the Adriatic with the Ionian Sea to the south. The chief ports are Venice, Brindisi, Trieste, Ancona, and Bari in Italy, and Rijeka in Croatia. The sea is about 805 km/500 mi long; area 135,250 sq km/52,220 sq mi. Fishing is an important activity; sardines, lobsters, and tuna are the chief catch.

The chief rivers flowing into the Adriatic are the Po and Adige in Italy; they have caused considerable silting. Pollution from organic waste and nutrients has caused eutrophication (rapid algae growth leading to oxygen depletion) in the shallow northern areas. The Adriatic has little tidal flow, and the water is very salty and rich in fish.

The north coast is marshy with lagoons; the east coast is rocky and has many small offshore islands. The Italian coast is generally low-lying. The Croatian coast, which has many offshore islands and sheltered bays, is a popular tourist area. The sea takes its name from the Italian town of Adria, formerly a port but no longer on the coast because of silting by the River Po.