The river Danube and the South Dobrogea.
The northern boundary of Bulgaria that separates it from Romania is the Danube River. The Danube River is a very important river that flows through several countries before it reaches the Mediterranean Ocean.
Canada forms the northern boundary of the United States.
This is the river Danube.
This boundary is mainly Danube; and a in the South of Dobrogea a terrestrial border.
The sea that forms the northern boundary of Africa is the Mediterranean Sea. The countries of Morocco, Algeria, Tunisia, Libya and Egypt border it.
This is the river Danube.
The Arctic Ocean
red river
The western boundary of Romania is with Hungary.
The 42nd northern latitude
The sea that forms the northern boundary of Africa is the Mediterranean Sea. The countries of Morocco, Algeria, Tunisia, Libya and Egypt border it.