Danube River Along Borders of Romania, Serbia and Bulgaria – March 31st, 201044.2N 22.7E
The Danube River winds its way across this orthorectified image, providing the border between Romania (above), Serbia (left) and Bulgaria (lower center to right). It is the longest river in the European Union. Although only three countries are visible here, the Danube actually flows through or along the border of 10 different nations.
The river originates in the Black Forest in Germany and flows eastwards for a distance of some 2850 km (1771 miles), passing through four Central and Eastern European capitals, before emptying into the Black Sea via the Danube Delta in Romania and Ukraine.
Of the 10 countries through which or along the borders of which it passes, the following percentage of its length is found in each: Germany (7.5%), Austria (10.3%), Slovakia (5.8%), Hungary (11.7%), Croatia (4.5%), Serbia (10.3%), Romania (28.9%), Bulgaria (5.2%), Moldova (0.017%), and Ukraine (3.8%).