Danube
Europe's second river, flowing through ten countries
The Danube touches more countries than any other river on Earth, flowing through ten of them on its way across Europe, and for two thousand years it has been a frontier, a trade route and a thread linking very different worlds. It rises in the Black Forest of Germany and runs eastward through the heart of the continent, past four national capitals, before fanning into a great delta on the Black Sea. Where the Rhine flows west into the Atlantic world, the Danube flows east into the Balkans and beyond.
The Danube runs about 2,850 kilometers, second in Europe only to the Volga. From its modest German headwaters it gathers Alpine and Carpathian tributaries, swelling into a major navigable river by the time it reaches Vienna and Budapest. It carves a dramatic gorge, the Iron Gates, through the Carpathians on the Serbian-Romanian border, now dammed for hydroelectricity and shipping. At its mouth it spreads into the Danube Delta straddling Romania and Ukraine, a vast wetland of reeds, lakes and bird colonies, one of the best-preserved in Europe.
The river was the northern frontier of the Roman Empire, its bank lined with forts that grew into cities like Vienna, Budapest and Belgrade. Through the centuries it carried grain, salt and armies, and bound together the multinational Habsburg lands. Today the Rhine-Main-Danube Canal links it to the North Sea, completing a waterway across the continent, and the river is a corridor of trade and cruise tourism. Its delta, shared and protected, remains one of Europe's great refuges for wildlife.