Berlin was a nerve centre for the Nazi movement during WWII. The city became a top target for allied forces looking to weaken the Third Reich’s defences.
Much of the city was obliterated by bombings and attacks, forcing Berliners to take shelter far beneath the streets of the German city.
One of the last remaining civilian air raid shelters is open for the public to explore after having been restored and cared for by Berliner Unterwelten, an organisation dedicated to preserving Berlin’s underground history.
Hundreds of people walk past this green door in Berlin's Gesundbrunnen Underground railway station every day. But few know what lies behind it.
Through the doors is a vast network of abandoned tunnels. Tunnels that were a safe-haven for thousands of Berlin's civilians whenever the air raid sirens sounded.
Berliners spent their waking hours in these cold, damp tunnels. The living conditions were cramped, air supplies were depleted, and the constant clanging of air vents and overhead bombings made for appalling living conditions.
The Nazis who signposted the underground hideaway included subtle hints of German propaganda. They refused to adapt to an increasingly European way of life. They insisted on using the word 'abort' for toilet, instead of 'toilette,' which they deemed too French.
The bunker has been immaculately preserved by Berliner Unterwelten. A group of more than 350 history enthusiasts from all walks of life. They research and document Berlin's historical underground sites.
They have managed to keep many artefacts in near original condition, including cutlery and crockery sets. The shelter is like a scene frozen in time.
The bunkers went untouched from when the Berlin Wall was built in 1961 right through to 1997 when Berliner Unterwelten acquired the site.
Photos, weapons and bombs have also been preserved. Fluorescent paint used as a lighting system in what would have been an otherwise pitch black envrionment remains.
When people emerged from these underground shelters, there was a high chance their house would be little more than a pile of rubble as 80% of Berlin was bombed in WWII.
The tower was one of three allegedly bomb-proof fortresses built on Hitler's orders in an attempt to protect the Nazi stronghold from aerial invasion.
As well as mounted anti-aircraft cannons and room for hundreds of military personnel, these vast structures could also house up to 15,000 civilians.
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