Danube
The Danube flows through many cities, including four national capitals (shown below in bold), more than any other river in the world. Ordered from the source to the mouth they are:
The Danube is navigable by ocean ships from the Black Sea to Brăila in Romania and by river ships to Kelheim, Bavaria, Germany; smaller craft can navigate further upstream to Ulm, Württemberg, Germany. About 60 of its tributaries are also navigable.
List of crossings of the Danube
This is a list of crossings of the Danube river, from its source in Germany to its mouth in the Black Sea. Next to each bridge listed is information regarding the year in which it was constructed and for what use it was constructed (foot bridge, bicycle bridge, road bridge or railway bridge), and the distance from the mouth of the river in kilometres where available.