The Adriatic Sea is a body of water separating the Italian Peninsula from the Balkan Peninsula. It is the northernmost arm of the Mediterranean Sea, stretching from the Gulf of Venice to the Strait of Otranto. The sea contains over 1,300 islands, mostly located along the Croatian coast. Historically, the Adriatic was the heart of the Republic of Venice's maritime empire, serving as a vital trade link between Europe and the East. Today, it is famous for its clear blue waters and historic coastal cities like Dubrovnik and Split. The sea's salinity is higher than the ocean average, and it features a unique circulation pattern driven by the 'Bora'—a cold, strong northeasterly wind. Environmental concerns include the rising sea levels threatening the city of Venice and the impact of heavy cruise ship traffic on the fragile marine ecosystem and coastal heritage sites.