Rhine–Main–Danube Canal

Lore & Background

The Rhine–Main–Danube Canal (German: Rhein-Main-Donau-Kanal; also called Main–Danube Canal, RMD Canal or Europa Canal) is a canal in Bavaria, Germany. Connecting the Main and the Danube rivers across the European watershed, it runs from Bamberg via Nuremberg to Kelheim. The canal connects the North Sea and Atlantic Ocean to the Black Sea, providing a navigable artery between the Rhine delta and the Danube Delta. Projects for connecting the Danube and Rhine basins by canal have a long history. The last section, between Nuremberg and Kelheim, became politically controversial in the 1970s and 1980s, mainly because of the 34-kilometre section through the Altmühl valley. The canal's route follows the Regnitz valley from Bamberg to Fürth, then the Rednitz valley to beyond Roth, crosses the Franconian Jura, and joins the Altmühl near Dietfurt, continuing to Kelheim. The canal has 16 locks, with lifting heights up to 25 meters, managed from four remote control centres.

Reader's Guide

The Rhine–Main–Danube Canal is significant as a major European waterway that connects the North Sea and Atlantic Ocean to the Black Sea, enabling navigation from Rotterdam to the Danube Delta. Its legacy includes ongoing controversy over environmental impact and economic viability. The canal also supports tourism, and remnants of the Ludwig Canal still exist, with some locks functioning and a cycle track on the towpath. The canal's construction included extensive habitat compensation, reflecting modern environmental concerns.

Did You Know?

• The canal has 16 locks, with a maximum lift height of 24.67 meters at the Hilpoltstein lock.
• Almost 20 percent of the construction cost went for environmental protection projects.

A Thousand-Year Dream of Connecting Two Seas

That medieval effort was the first in a long line of attempts to bridge the European watershed. The next major chapter came in the mid-nineteenth century, when the Ludwig Canal was built between Bamberg and Kelheim under King Ludwig I of Bavaria. Yet its narrow channel, numerous locks, and chronic water shortages at the summit quickly rendered it uneconomical, especially as railways spread across southern Germany.

Three Decades of Construction and Controversy

Yet the war interrupted those early efforts, and the Mindorfer route was ultimately discarded. The last stretch, running from Nuremberg to Kelheim, proved the most contentious. A 34-kilometre segment threading through the Altmühl valley sparked intense political debate throughout the 1970s and 1980s, as environmental concerns clashed with economic arguments for a continuous waterway.

Engineering at the Summit

The canal's cross-section is predominantly trapezoidal, measuring 31 metres across the bottom and 55 metres at the water surface, with a depth of four metres and a side slope of one to three. This makes it the highest point on Earth currently reached by commercial watercraft originating from the sea. To sustain the summit pound, water is pumped upward from lower stretches and supplemented by local natural sources; when those fall short, a pumped-storage reservoir called the Dürrlohsee, positioned even higher than the summit pound, provides the additional volume needed.

Locks, Water Conservation, and the Old Canal's Ghost

Sixteen locks line the canal's route, with individual lifting heights reaching up to 25 metres. Their operation is coordinated from four remote control centres—Neuses, Kriegenbrunn, Hilpoltstein, and Dietfurt—each staffed by two workers during the day and one at night. Thirteen of the sixteen locks incorporate water-saving technology: during the down cycle, the top and then middle thirds of the chamber water are piped into side tanks, and those tanks refill the chamber on the up cycle, conserving the fresh water that would otherwise be lost. Meanwhile, a legacy of the older Ludwig Canal persists in the landscape. Approximately 60 kilometres of that nineteenth-century waterway still survive in good condition between Nuremberg and Berching, with some locks still operational and sections of the towpath converted into a cycle track. At Pollanten the old and new canals run close together, flowing in parallel for several kilometres before converging roughly five kilometres south of Berching.