The Danube River is a very important river in Europe and is the longest river in the European Union. The Danube stretches from Germany through 4 country capitals, several different countries and finally ends at the Black Sea. It is on the border of Germany, Austria, Slovakia, Hungary, Croatia, Serbia, Romania, Bulgaria, Moldova and Ukraine.

The Danube River can be divided into three different sections. The upper section of the river runs from its start to the Devin gate. The next section, the middle section, goes from the Devin Gate to the Iron Gate and the last section, the lower section, goes from the Iron Gate to Sulina.

The river is deep enough for large ocean liners to travel to Romania. Once you have arrived in Braila, you have to switch to smaller boats that can take you to Bavaria. Eventually you will have to switch to an even smaller boat in Kelheim to go down the river to Germany.

There are several islands in the Danube River. Some of these islands are Donauinsel, Sarengrad Island, Great War Island, Vardin Island, Ostro, Margarita Island, Vukivar Island, Gran Braila Island, Csepel Island, Belene Island, Balta Ialomitei and Ada Kaleh.

In the 1990s, the Danube river was connected to the trans-European inland waterway due to the construction of the Rhine-Main-Danube canal. This channel provides a link from the Black Sea to the North Sea. Since the Danube is used for commercial purposes, it is also part of the European transport corridor. Three artificial waterways on the Danube include the Rhine-Main-Danube canal, the Danube-black canal, and the Danube-Tisa-Danube canal.

The Danube River and its tributaries and groundwater are all protected by the International Commission for the Protection of the Danube River. This commission is made up of 14 countries that are dedicating themselves to the conservation and sustainable management of the river.