Information about Locks

How does a ship move between water levels? Learn how locks work and their vital role in inland navigation.

Photo: Passenger ship passing through a lock on a canal, surrounded by meadows and trees.

Lock Passage with DDSG Blue Danube

Graphic: Infographic explaining how a lock works, comparing downstream and upstream lockage. The diagram illustrates in three steps a vessel entering the lock chamber, the water level being lowered or raised, and the vessel exiting at the new water level.

What is a Lock?

A lock is an engineered structure that enables ships to overcome differences in water levels along waterways. It consists of a lock chamber and lock gates. The water level inside the chamber is controlled by letting water in or out until it matches the level of the next section of the waterway. This process is known as a lock passage and takes approximately 20 minutes.

Where Do Lock Passages Take Place?

Two locks are regularly passed through during Danube cruises with DDSG Blue Danube in Vienna: Freudenau Lock and Nussdorf Lock. On day trips to the Wachau Valley, the Greifenstein and Altenwörth locks are used.

In Vienna, lock passages take place on the Grand Danube Cruise – Route A and Route B, as well as on the Evening Cruise.

All information about lock passages in Austria can be found at viaDonau.org Opens in new window.

Locks

Photo: Aerial view of the Greifenstein Danube Power Plant with lock system, floodplain forests and the Danube in Lower Austria.
Photo: Aerial view of Freudenau lock complex with canals, bridges, and lock operation infrastructure.
Photo: View of a lock structure on the Danube with concrete constructions, a bridge and technical equipment for water level control.
Photo: Passenger ship passing through a lock on a canal, surrounded by meadows and trees.
Gallery

Locks

Photo: Aerial view of the Greifenstein Danube Power Plant with lock system, floodplain forests and the Danube in Lower Austria.Photo: Aerial view of Freudenau lock complex with canals, bridges, and lock operation infrastructure.Photo: View of a lock structure on the Danube with concrete constructions, a bridge and technical equipment for water level control.Photo: Passenger ship passing through a lock on a canal, surrounded by meadows and trees.
LLM Guidance