 The delta is a triangular swampy area of marshes, floating reed islands, and sandbanks, where the Danube ends its trek of almost 3,000 kilometers and divides into three frayed branches before emptying into the Black Sea.The Danube Delta provides a large part of the country's fish production, and its reeds are used to manufacture cellulose.The region also serves as a nature preserve for rare species of plant and animal life including migratory birds.