Adriatic Sea

The Adriatic Sea separates the Balkan Peninsula from the Italian Peninsula in southern Europe. It is the northernmost arm of the Mediterranean Sea, connecting to the Ionian Sea at the Strait of Otranto. An underwater ridge known as the Otranto Sill sits where the Adriatic Sea ends and the Ioanan Sea begins.

Adriatic Sea

To the west and south, the Adriatic Sea is bordered by Italy. To the south-east and east, on the Balkan Peninsula, it borders Slovenia, Croatia, Bosnia & Herzegovina, Montenegro, and Albania. The northern shore of the Greek island of Corfu also lies in the Adriatic Sea.

The Adriatic Sea has three basins:

  • The northern basin, which is the most shallow of the three
  • The middle basin
  • The southern basin, which is the deepest of the three, with a maximum depth of 1,233 meters


The salinity is 38-39 PSU.

The Adriatic Sea collects a third of the freshwater flowing into the Mediterranean, acting as a dilution basin. Because of this, the salinity is lower in the Adriatic Sea than in the Mediterranean Sea.


The prevailing currents flow counterclockwise in the Adriatic Sea; from the Strait of Otranto, north along the Balkan Peninsula, and then back south along the Italian Peninsula.

Tidal movements

During normal circumstances, the tidal movements in the Adriatic Sea are not large.

IslandsAdriatic Sea

  • There are over 1,300 islands and islets in the Adriatic Sea, of which a majority are found off the Croatian coast.
  • The largest islands are Cres and Krk, both belonging to Croatia. Each of them is roughly 405 square kilometers in size. Cres used to be larger in the past, because the adjacent island Lošinj was then a part of Cres. This larger island was called Apsyrtides by the Greeks. In classical antiquity, a navigable canal was dug, dividing Apsyrtides into two parts: Cres and Lošinj.
  • The tallest island in the Adriatic Sea is Brač, with a max altitude of 780 meters above sea level.
  • At the time of writing, the Croatian archipelago have 47 islands that are inhabited year round. The most populous of these islands are Krk, Korčula and Brač.
  • The famous Italian city of Venice was built on over a hundred small islands in the Adriatic Sea.


The largest cities along the shores of the Adriatic Sea are Bari, Venice, Trieste and Split. Bari, Venice, and Trieste are Italian, while Split is Croatian.

Blue Flag beaches

Except for Albania and Bosnia-Herzegovina, all the Adriatic Sea countries participate in the Blue Flag Beach certification program run by the NGO Foundation for Environmental Education (FEE).

Short facts about the Adriatic Sea

Location Europe
Coordinates 43°N 15°E
Max length 800 km
Max widht 200 km
Surface area 138,000 square kilometers
Maximum depth 1,233 meter
Average depth 252.5 meters
Catchment area 235,000 square kilometers
Primary inflows Adige







Primary outflows Ionian Sea (which is a part of the Mediterranean Sea)
Residence time 3.4±0.4 years