The Adriatic Sea is a part of the Mediterranean Sea. It is positioned between the eastern coastline of Italy and the coastline of countries of the Balkan Peninsula (Slovenia, Croatia, Bosnia and Herzegovina, Montenegro and Albania). The Adriatic coastline is by far Croatia’s most popular tourist region with around 11 million tourists each year. The Adriatic Sea is a part of the Mediterranean Sea. It is positioned between the eastern coastline of Italy and the coastline of countries of the Balkan Peninsula (Slovenia, Croatia, Bosnia and Herzegovina, Montenegro and Albania).