The Adriatic sea is an arm of the Mediterranean sea. It begins at the Otranto strait in the south and stretches 783 km northwest into Europe. The sea was named after a small town of Adria in northern Italy.
The main bordering countries are Italy on the west, Croatia and Montenegro on the northeast and Albania on the southeast. Slovenia and Bosnia and Herzegovina each also have a patch of Adriatic coast, but they don't reach international waters via their own territorial waters.
The Adriatic is widest in the central part between Montenegro and southern Italy (up to 225 km), but the islands near the eastern coast reduce the width of the open sea to about 140 km. The aforementioned Otranto strait is the narrowest point, only 93 km wide.
The depth decreases from south to north: the northern part of the sea isn't particularly deep, but the southern gets as deep as 1280 meters, which results with 239 m average depth.
The Adriatic sea is characterized by clear and blue water. The transparency is 20-33 meters on the north, and up to 56 meters on the south. This also means that there isn't an awful lot of sea life in it.
Furthermore, the water is rather salty (salinity is 38 which is above average), which is because it's a "closed" sea, and a warm one. There aren't a lot of rivers flowing into it (that would bring colder water, and also reduce brininess). The average temperature in the summer ranges from 22 to 25 degrees Celsius, while the winter temperatures range from 5 to 15 degrees.
The sea currents are weak. They move counterclockwise, the warm water comes in from the Ionian sea at Otranto, goes through the indented east coast, cools down and goes back to the Ionian sea by the west coast.
The tides aren't high, ranging from 25 cm on the south to 80 cm on the north. The tidal wave revolves around the amphidromic point in the northwestern part of the sea, near the Italian city of Ancona.
Major winds blow from the northeast ("bura" or "bora") and southeast ("sirocco", "siloco" or "jugo"), and they sometimes cause suspension of maritime traffic in the winter. Two other winds blow, "maestral" from the west in the summer and "lebić" from the southwest (used to cause damage to ports). The waves are larger on the western side of the sea, up to 5m if caused by bura.
There are over a thousand islands in the Adriatic sea.
Major cities on the coast include Trieste, Venezia, Rimini, Ancona, Pescara and Bari in Italy; Koper in Slovenia; Rijeka, Pula, Zadar, Sibenik, Split and Dubrovnik in Croatia; Bar in Montenegro; and finally, Durresi in Albania.
The largest rivers that flow into the Adriatic sea are Po, Piave, Neretva, Drim and Viose.