In the bulging underworld far below trees’ toes at Niederlehme, huge hollow halls strain to hold the souls of tormented soldiers trapped in the heavy nothingness of perpetual darkness.

Neither heaven nor hell nor any place of this world, these massive metal chambers are only gained through locked portals plunging deep beneath forested hills that give scant clue to their contents. Weird pipes in otherworldly formations jut above the ground to hint of their presence. But nothing can prepare you for what lies below.

This, ladies and gentlemen, and those who are neither, is Treib- und Schmierstofflager 44 (fuel and lubricant store 44), also known as TSL 44, a former oil and fuel storage facility used by Nazi Germany, then East Germany’s armed forces.

There are at least five giant tanks at the site – two round fuel tanks each with a capacity of 7,700 cubic meters and each with a magnificent ladder reaching for the top in the middle, puncturing the vast emptiness, and at least three smaller (yet still huge) rectangular tanks.

What the hell are they doing there?

I’m relying on others’ research for this, but apparently this facility started under the umbrella of the Nazis’ Paraxolwerk Niederlehme armaments factory, which produced pentaerythritol – a raw material for the explosive material pentaerythritol tetranitrate – from 1940-45.

The area where the tanks are was about one kilometer south of the main factory and it served as a storage facility for methanol, a raw material for the production of formaldehyde, which was converted to pentaerythritol.

They could have saved themselves the bother. The Soviets took over after the war and destroyed pretty much anything they couldn’t loot, though the underground tanks survived, presumably because it would have been a bit risky trying to blow them up and bringing them back to Moscow on the train wasn’t really an option.

The East German Kasernierte Volkspolizei (Barracked People’s Police) took over what was left in 1951. Then, when they were rebranded the Nationale Volksarmee (National People’s Army, NVA) in 1956, they started expanding the site and building new buildings to replace those destroyed by their good ol’ Soviet comrades.

The former methanol storage facility became Treib- und Schmierstofflager 44 (TSL 44) in 1964 for East German army’s air force (Luftstreitkräfte, or LSK). More modifications and additions were made, including the installation of the two giant round fuel tanks. All tanks were used to store jet fuel, or kerosene.

It was apparently brought to the site by oil tankers and unloaded at a specially built pump bunker at Niederlehme, where a pressurized line ensured it reached the storage tanks at TSL 44, and more pressurized lines then helped it out again when it was needed.

With the end of East Germany, came the end of the East German army – and the need for all that jet fuel. There was no country to defend any more.

The new reunified German Bundeswehr took one look at TSL 44 and said, “Nee, das brauchen wir nicht.” It was promptly abandoned and discarded – a final insult after so much went into it.

Someone tried reviving it as an equestrian center but all that horsing around never took off. In 2014, the local Königs Wusterhausen council approved a plan to turn TSL 44 into a holiday and leisure center. By the looks of things however, the holiday started before any work was done.

The smell of gasoline still wafts through the dark emptiness of the giant metal caverns, and the floor bounces playfully underfoot, belying some hidden hell lurking below. Make a sound and it echoes through the vast empty chamber, returning from the dark void because you’re the only thing there. Best stay silent if you want to get out again.

• the What: Niederlehme Treib- und Schmierstofflager 44, aka TSL 44, a former oil and fuel storage facility that the Germans used to store raw materials for an armaments factory during the war, then jet fuel for the East German army after it.
• Where: Niederlehme, 15713 Königs Wusterhausen.
• How to get there: You’ll need to get a regional train to Königs Wusterhausen – the RE7 to Senftenburg goes from Zoo, Hauptbahnhof, Alex and Ostbahnhof – and then cycle to Niederlehme. Just follow the signs north for Niederlehme, then turn right at the roundabout onto Spreenhagener Straße. Follow this past some houses on your right and left before you get to a fork in the road. Turn right and follow that till you can’t go anymore. You’re there. Here it is on a map so you don’t get lost.
• Getting in: All the buildings above ground are easy to get into, you won’t have any problems there. The tanks are a different matter. One big round rank is accessible through a portal at ground level, the other only through the top by descending the ladder. It’s a bit daunting, you don’t want to lose your grip and plunge to your death in the dark depths below! The other tanks are accessible through the holes some kind passerby cut in the metal grids guarding the doorways cut into the hills. Mind your jacket, the metal is sharp. I cut the shit of mine. You’ll need to go down steps, a ladder, then crawl through a short rusty tunnel to get into the tank.
• When to go: Daytime is best if you want to see anything outside. Otherwise it doesn’t matter. The tanks are dark 24/7.
• Difficulty rating: 8/10. There is a bit of effort involved getting into the tanks.
• Who to bring: Someone. Best not to go on your own in case you get stuck in a tank. There ain’t no mobile signal and no one would hear your screams. Don’t wear your Sunday best or any clothes you’re precious about. Otherwise bring some snacks for the road, a camera to take snaps on the road, water, beer, compass, and a bag of crumbs so you can find your way back out again.
• Dangers: There is a serious danger of falling if you’re not careful. And if you fall, there’s a serious danger of serious injury. I’m serious, be fucking careful. That’s it, that danger precludes the need for any others.

Many thanks to Peter and O for the tip, and once again to the over-worked Mark Rodden for proof-reading! And also to photographer extraordinaire Neil Hoare for the pleasure of his company (for you definitely shouldn’t go alone) on the last two visits. You can see a couple of his photos here.