Gabcikovo Lock on the Danube River

The Danube River is the longest river within the European Union. It flows through 10 countries, more than any other river in the world, and through many major national capitals: Vienna (Austria), Bratislava (Slovakia),  Budapest (Hungary), and Belgrade (Serbia). Originating in the Black Forest of Germany, the Danube flows southeast for 1,780 miles (2,860 km) before emptying into the Black Sea. Historically important as a means of transport and trade, it is also called “the river of kings” because it was the preferred route of travel by rulers since ancient times.

Gabcikovo (gob chi KO vo) Lock is the only lock on the Danube River between Vienna and Budapest. The difference in elevation is 59 feet (18 m). It is part of a hydroelectric project that produces 10% of Slovakia's electricity.

HOW THE LOCK WORKS

There is a chamber with heavy gates at each end. Your boat enters the gates at its water level.

The gates close, and the lock keeper opens valves that let water pour out of the lock chamber.

The boat starts its descent.

The boat descends lower and lower as the water pours out.

You sit there while the lock chamber empties. The Control Tower overlooks the lock. A radar antenna, useful for collision avoidance, is on the front of the boat.

The Control Tower and observers on the “bridge”

The water level is not yet low enough for the gates to open. 

Looking straight up at the wall of the lock chamber.

I felt nervous when the boat was at its lowest level. If anything happened, say, if the chamber wall collapsed inward, we couldn’t have been in a more vulnerable position. Nobody around me shared this worry; on the contrary, they reassured me that nothing could go wrong.* I kept track of the locations of the service ladders (on the left in the pic--also, notice the cracks in the walls), just in case we needed a quick exit from the boat. 

When it matches the new water level, the other gates open, and you move on. The water is entirely moved by gravity; there are no pumps. (Of course, the process is reversed if the boat must be elevated to meet the new water level.)

The gates continue to open.

The gates are wide open now.

Looking back to where the boat entered the lock

Looking forward to the place the boat will exit the lock

Passing the exit gates with observers on the bridge overhead

Past the gates 

Whew! We made it.

On our way once again

* FYI, there have been a number of accidents near and within locks; however, so far the accidents have been due to human error on the part of the boat pilots and not to failure of the lock or lock chamber itself. However, in July of 2014, river boats were stuck on the Danube for days  because the Gabcikovo Lock was broken. Passengers disembarked and were bussed to their destination. Of course, seeing the Danube from the bus was not nearly as enjoyable as seeing the Danube from the boat.