By Viktor Krizik
Umbrella and garbage by the Danube River, Belgrade, Serbia. Europe’s second-longest river flows through 10 countries and 4 capital cities, and is the source of drinking water for 20 million people. In 1998, threats from overfishing, pollution and hydroelectric dams prompted 14 states to sign a convention that is taking an integrated approach to managing the whole river basin – and the landscapes within it.