The Danube Delta is situated in the eastern part of Romania, in the Tulcea County.

The Danube Delta has the third ecological significance among the 300 UNESCO reserves in the world. Through UNESCO resolution of 02.02.1999, the Danube Delta reserve received the international certificate of Biosphere Reserve.

The Danube Delta is home to more than 300 migratory and permanent bird species; 160 kinds of fish that include caviar-bearing sturgeon and 800 plant families. This wetlands preserve covers more than 1,678,000 acres (2,622 sq. miles) comprising channels and canals widening into tree-fringed lakes, reed islands, numerous lakes and marshes, oak forests intertwined with lianas and creepers, desert dunes and traditional fishermen villages.

The Danube Delta has a surface of 5.640 km2, the second largest delta in Europe. The surface that is included in the Danube Delta Biosphere Reserve (D.D.B.R.) is of 4.178 km2, only 3.446 km2 of which are on Romanian territory.

The Razim-Sinoe lagoon system is also included in the Danube Delta and it comprises Razim, Golovita, and Zmeica and Sinoe lakes. About the Lake Razim`s name there are more variants: its name comes from that of the Russian orthodox of old rite revolutionist Stepan Razim that was killed on the lake`s borders. The name of Razelm was used by the Turks to designate this lake.

The Danube Delta was formed at the Danube river mouth that flows in the Black Sea. The river is the second in length in Europe after the Volga and it springs from the Black Forest Mountains (Schwarzwald) in Germany and travels 2.860 km until its river mouth, crossing 17 countries. Due to the mud deposits carried by the river, the delta`s surface has grown in time (it grows with 40 m per year), most of its relief is formed of channels, lakes, sand dunes.