The sea that lies between Italy and the Balkan Peninsula is the Adriatic Sea. Stretching from the Po River in Italy to the Montenegro coastline, the Adriatic is an important body of water historically and economically. It facilitates trade and tourism with its numerous coastal cities, including Venice, Dubrovnik, and Split. The sea is also renowned for its beautiful islands, crystal-clear waters, and rich marine biodiversity, making it a popular destination for travelers.