The Rhine–Main–Danube Canal (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 the Atlantic Ocean to the Black Sea, providing a navigable artery between the Rhine delta (at Rotterdam in the Netherlands), and the Danube Delta in south-eastern Romania and south-western Ukraine (or Constanța, through the Danube–Black Sea Canal). The present canal was completed in 1992 and is 171 kilometers long.

The height difference along the north ramp of the canal—from the Main at Bamberg to the crest elevation—is 175 meters, with 11 locks. From the crest elevation down to the Altmühl at Dietfurt is a drop of 51 meters through three locks. The further difference in elevation of 17 meters along the Altmühl, with two more locks, makes a total of 68 meters for the south ramp. This means that the Danube end of the canal is 107.3 meters above the level of the Main end.

Along the course of the canal, there are 16 locks with lifting heights of up to 25 meters. The 16 locks are managed from four remote control centers.

The long-distance Challenge Roth triathlon, which is held annually in July, includes a 3.8-kilometer (2.4 mi) swim in the Main-Danube Canal at Hilpoltstein. The canal is closed to vessel traffic during the race. An approximately 14-kilometer-long section of the marathon route runs along the canal from the Hilpoltstein lock to the Leerstetten lock.

According to Wikipedia