The sea that lies between Italy and the Balkans is the Adriatic Sea. This body of water extends from the Po River in Italy to Montenegro and is known for its clear waters and picturesque coastline. The Adriatic Sea has been historically significant for trade and transportation, connecting various nations in Southern Europe. It features numerous islands and beautiful coastal towns that attract tourists, including Sicily and Venice. The sea's ecological importance is highlighted by the diverse marine life found in its waters.