A sprawling concrete relic of the Third Reich has ignited a fierce preservation battle in Berlin, drawing sharp condemnation from historians and conservationists across Europe. The Flak tower at Humboldthain, one of six colossal anti-aircraft fortresses built by Nazi Germany, is currently slated for partial demolition to make way for luxury apartments. The move has been labelled “absolute madness” by UK heritage experts, who warn that erasing such structures risks sanitising history.
The twin towers, each rising 40 metres above the Berlin skyline, were constructed in 1941 using forced labour. Their metre-thick walls were designed to withstand direct bombing raids and served as both air defence shelters and propaganda symbols. After the war, the Allies debated their fate. Some were dynamited, but the Humboldthain bunker survived due to its sheer size and the threat of bringing down nearby buildings. For decades, it has stood as a silent, unyielding monument to catastrophe.
Now, a developer plans to cut a opening into the western tower to create a residential block. This would remove a significant portion of the original concrete facade and internal structures. Local authorities have approved the scheme, arguing the site is not a listed monument and that the new housing is desperately needed.
“This is historically illiterate,” said Dr. Eleanor Ashcroft, a historian at the University of Cambridge specialising in memory studies. “These bunkers are not simply Nazi architecture. They are physical repositories of collective trauma. To chip away at them for profit is to treat history as an inconvenience. It redefines madness.”
British conservation group Historic England has added its voice, with a spokesperson noting that “the preservation of difficult heritage requires courage, not convenience. We would urge Berlin to reconsider. The bunker should be a site for reflection, not rubble.”
The controversy reflects a deeper tension in Germany’s long struggle with its past. National law mandates the preservation of architectural heritage only if it holds “artistic, historical, or scientific value.” The Flak towers, designed for slaughter, have been judged by some as lacking aesthetic merit. Yet they are unarguably witnesses to the regime’s industrialised violence.
I visited the Humboldthain bunker in early spring. The air inside is cold and damp; the concrete seems to sweat. Graffiti covers the lower walls, layered over decades: punk tags, anti-fascist slogans, an anarchist symbol. On the roof, a hawthorn tree has rooted into a crack and grown to waist height. Nature and history fight for space.
A local resident, Klaus Weber, stood watching as surveyors measured the eastern tower. “My father was a soldier,” he said. “He never spoke of the war. This bunker reminds me of his silence. If they destroy it, what will we tell our children? That we preferred a kitchen island to a memory?”
The developer, Prestige Wohnbau, issued a statement claiming the project would “repurpose a disused structure with sensitivity” and include a small memorial inside the apartment complex. Critics were unconvinced. “You cannot integrate a memorial into a luxury penthouse,” said Ashcroft. “One demands quiet. The other charges for panoramic views.”
This battle comes as Europe grapples with a wave of heritage removals, from colonial statues to Soviet war memorials. The Humboldthain bunker occupies a unique space: it is neither honourific nor decorative. It is brute function frozen in concrete. To keep it means to accept that some places must remain uncomfortable.
The Flak towers were designed by Albert Speer, Hitler’s architect, and built by prisoners from concentration camps. They are engineering marvels and moral tombs. In 2019, Berlin declared the city’s three remaining bunkers “protected against removal” in theory, but the ruling allowed for modifications. That loophole is now being exploited.
“This sets a terrible precedent,” said Markus Schmidt, a Berlin city councillor who voted against the development. “If we allow the destruction of our most difficult sites, we lose the ability to confront what happened. We become a city that only wants to remember the easy parts.”
As the diggers prepare to move in, the UK’s heritage experts have offered an alternative: purchase the site for a museum, funded through international cultural donations. No buyer has stepped forward. The clock ticks on another piece of history that many would rather forget.
But as I looked up at the grey monolith, its walls pockmarked by bullets and weather, I felt the weight of the word “preservation”. It is not about keeping something beautiful. It is about refusing to let the story disappear.
