The Adriatic Sea (Croatian: Jadran) is part of the Mediterranean Sea and lies between the Apennine peninsula (Italy) to the west and the Dinara Mountains to the east, spreading in the direction NW-SE. The Adriatic Sea is 783 km long and 248.3 km wide, with a surface of 138,595 km2. It was named after the settlement Adria in the northern Adriatic, an important port during the classical period (6th-4th century BC).
The majority of the Adriatic islands are located in the eastern part of the sea, belonging to the territory of the Republic of Croatia. The total number of Croatian islands is 1,246. This number also comprises 642 rocks and 525 islets, while only 47 islands are inhabited.
The Croatian islands can be divided into two main regional groups, based on their cultural and economic connections: the Kvarner Bay islands in the northern Adriatic (Cres, Lošinj, Krk, Rab, and the Pag island group) and the Dalmatian islands (Brač, Vis, Korčula, Lastovo, and the Hvar island group), including the islands gravitating towards various Dalmatian coastal towns, such as Zadar, Biograd, Šibenik, Trogir, Split and Dubrovnik.