Main-Danube Canal, also called Europa Canal, German Main-Donau-Kanal or Europa-Kanal, Main-Danube Canal: lock and viewing platform [Credit: Travel Ink/Gallo Images/Getty Images] commercial waterway in the southern German state of Bavaria. Completed in 1992, the canal is 171 km (106 miles) long and runs from Bamberg on the Main River (a tributary of the Rhine River) to Kelheim on the Danube River, permitting traffic to flow between the North Sea and the Black Sea. It thus creates a 3,500-km (2,200-mile) waterway that runs through 15 countries and can accommodate barges carrying up to 2,425 tons of bulk cargo.