The “Valentin” bunker, 426 metres long and 33 metres high, was constructed using the forced labour of tens of thousands of people between 1943 and 1945. A satellite to the concentration camp Neuengamme was set up to accommodate the work, during which 1,600 people are thought to have died.
According to a report in Die Welt newspaper, the German Institute for Federal Real Estate (BIMA), which runs the site, now wants to rent parts of the bunker for commercial use.
But, according to Georg Skalecki, director of the local State Office for the Preservation of Historical Monuments, this would involve the destruction of walls and fences, seriously damaging the building's character.
“You would no longer be able to take in the dimensions of the total work,” he told the paper. “You do need to be able to walk through it.”
The building was used as storage space by the German military until 2011. When BIMA took over management of the building, officials decided to rent out the main central hall as well as a three-storey side building. Skalecki has now submitted a legal objection to this.
The German state is also investing €3.8 million in a memorial and permanent exhibition on the Valentin bunker. This is expected to be completed in 2015. The building was opened for pre-arranged tours in May 2011.
The second-biggest above ground WWII bunker in Europe was originally intended as a huge wharf to build submarines, and would have become the biggest fortified wharf in the world.
But in March 1945, when the building was close to completion, having already used 1.2 million tonnes of concrete and steel, British bombs tore huge holes in the building.
The 4.5-metre thick ceiling was not yet reinforced enough to withstand the bombs, and the Nazi leadership was forced to give up the building site. By this stage in the war, Germany was in no position to begin mass-producing new submarines in any case.