The Adriatic Sea is part of the Mediterranean Sea and separates the Italian Peninsula from the Balkans. It is the northernmost arm of the Mediterranean Sea and has a surface area of around 138,000 km2. The sea borders the Ionian Sea through the Strait of Otranto. It is named after the Etruscan settlement of Adria. The sea contains over 1,300 islands, mostly located on the Croatian coastline. The Adriatic Sea has a lower salinity than the rest of the Mediterranean due to it collecting up to a third of the freshwater flowing into it. The sea is becoming a more popular tourist attraction, with especially Croatia’s tourism industry growing at a significant rate.