·         The Danube River Basin (DRB) covers an area of 801,463 km2, making it the second largest river basin in Europe, after the Volga.
·         The Danube is 2,870 km long and up to 1.5 km wide, with a depth of up to 8 meters.
·         This river originates in the Black Forest in Germany as two smaller rivers—the Brigach and the Breg—which join in the city of Donaueschingen. From there on it is known as the Danube. It flows eastwards emptying into the Black Sea via the Danube Delta in Romania.
·         The DRB is the world's most international river basin as it covers parts or all of 18 states comprising Albania, Austria, Bosnia-Herzegovina, Bulgaria, Croatia, the Czech Republic, Germany, Hungary, Italy, the Former Yugoslav Republic of Macedonia, Moldova, Poland, Romania, Serbia and Montenegro, the Slovak Republic, Slovenia, Switzerland and Ukraine. Following the independence of Montenegro, which was voted recently, the river basin will cover 19 states.
·         Some countries such as Austria, Hungary, Romania, Serbia and Montenegro and the Slovak Republic are almost completely situated within the DRB, whereas less than 5% of the territories of Albania, Italy, Macedonia, Poland and Switzerland lie in the basin.
·         The Danube River Basin is home to 81 million people with a wide range of cultures, languages and historical backgrounds. More than 26% of the overall basin population is Romanian. This is by far the largest population group in the DRB, followed by populations from Germany, Hungary, and Serbia and Montenegro.
·         There are 26 major tributaries of the Danube River, all of which have their own sub-basins. The Tysa (also called Tisza or Tisa) River Basin is the largest sub-basin in the DRB (157,186 km2). It is also the Danube’s longest tributary (966 km). The Sava River is the largest Danube tributary by discharge (average 1,564 m3/s) and the second largest by catchment area (95,419 km2).
·         In the DRB, there are several freshwater lakes of varying sizes. The most prominent are the ‘Balaton’ in Hungary (605 km2) and the ‘Neusiedlersee’ (also called Fertö tó), which is shared by Austria and Hungary (315 km2).
·         The Danube River is the single most important contributor to nutrient pollution in the Black Sea.

Source: The UNESCO Water Portal Weekly Newsletter No. 143