The Danube, celebrated in art and song, might be the world's most feted river. (After all, is there anyone who can't hum a few bars of the "Blue Danube Waltz"?) Meandering southeast from its origins in Germany's Black Forest, the Danube isn't Europe's longest river -- the Volga takes that honor. But, on its 1,775-mile course to the Black Sea, it flows through, or borders, 10 countries -- more than any other river in the world.
Along the way it shadows centuries-old storybook villages that appear unchanged by time and cuts through sophisticated world capitals, like Vienna and Budapest. Viking River Cruises' three most popular Danube River itineraries range from a 15-day Grand European Tour from Amsterdam to Budapest to two eight-day sailings, one from Passau, Germany, to Budapest, and the other from Budapest to Nuremberg, Germany.