The norther border of Bulgaria is delineated by the Danube river. I don't know of any other river that goes "through" BG.
There is no river called Bulgaria here
The River Nile does. It goes through Egypt and 1 more country then leads to the Mediterranean sea.
From Rila mountain crossing the full length of Bulgaria to be poured in BLACK SEA. Longest river in Bulgaria
They will float and end up wherever the river goes.
The Danube River forms part of the boundary between Bulgaria and Romania.
This river is called Danube. Its a northern border to Bulgaria and for Romania the south bound.
Daniube
Romania and Bulgaria border one another and are separated by the Danube. There is no country 'in the middle'.
Iskar river (if we dont count International river Danube)
no its in hungary
The River Danube forms the southern border of Romania. The next country to the South is Bulgaria. The River Danube is famous for the waltz of the same name.
Follow the river Danube to Belgrade, then turn to the river Sava, which will lead you to Slovenia.