Adriatic Sea, an arm of the Mediterranean Sea. The name comes from the city of Adria in northeast Italy. (It was once a port but is now 13 miles [21 km] inland due to silt deposition at the mouths of the Po River.) The Adriatic lies between Italy on the west and north and the Balkan Peninsula on the east. The only entrance to the sea is by the Strait of Otranto, which lies in the south between Italy and Albania and connects the Adriatic with the Ionian Sea.
The Adriatic Sea is about 500 miles (800 km) long, northwest-southeast, and up to 140 miles (225 km) wide. It has an area of approximately 51,000 square miles (132,000 km 2 ), slightly less than that of Lakes Superior and Michigan combined. The Adriatic is one of the shallowest parts of the Mediterranean, with an average depth of about 800 feet (240 m). The deepest spot, 4,034 feet (1,230 m), is about midway between Bari, Italy, and the coast of Montenegro.
In contrast to the northern part of Italy's Adriatic coast, where marshes and lagoons abound, the central and southern portions consist of sandy lowlands and beaches in many places backed by foothills of the Apennines. In Croatia and Serbia and Montenegro, where the Dinaric Alps descend abruptly to the sea, the coast is mountainous and studded with islands. Especially scenic is the Dalmatian region in Croatia, which has many resorts.
The Adriatic's balmy climate and excellent seaside and island resorts attract many tourists. Fishing and sponge diving are also important. Major cities and ports on the sea include Trieste, Venice, and Bari in Italy; Rijeka and Split in Croatia; and Durrës, the port city of Tiranë, capital of Albania.