Socialist Federal Republic of Yugoslavia
Regarding rivers, the Danube was navigable throughout its entire course in Yugoslavia, linking the ports of Belgrade, Novi Sad, and Vukovar with Central Europe and the Black sea. Long stretches of rivers Sava, Drava and Tisza were also navigable.
Main (river)
The Main is navigable for shipping from its mouth at the Rhine close to Mainz for to Bamberg. Since 1992, the Main has been connected to the Danube via the Rhine-Main-Danube Canal and the highly regulated Altmühl river. The Main has been canalized with 34 large locks () to allow CEMT class V vessels () to navigate the total length of the river. The 16 locks in the adjacent Rhine-Main-Danube Canal and the Danube itself are of the same dimensions.