I live in Hamburg, Germany. There are 2… things about this city which I feel could be combined into a decent SCP. So I'd like to take a minute to elaborate on those. The first is a subway platform which I frequently come through. It's a normal platform, and if you look across the tracks you see 2 more identical platforms, between some recently installed large screens displaying ads. All walls and ceilings inside the station bulge outwards, as the tunnels were originally dug as a circular tube. All walls except for the back wall of this platform, the wall opposite the tracks. This is a perfectly vertical, white tiled wall, noticeably newer than the surrounding construction. There are two gaps in wall, on at each end, just before the stairs leading up to the exit. These gaps consist of a fine mesh chain link fence, all the way to the ceiling. Through the fence you can see another identical platform, though unilluminated. Because these gaps are at the ends of the platform, you can clearly see the platform is connected to perfectly fine looking tunnels (although pitch black dark) in either direction. The chain link sections feature no signage whatsoever, and most strangely of all, no access doors.
So, thing 1 is an abandoned subway platform and tunnels, in a city that's currently spending 100s of millions on expanding the subway system.
Thing 2 is a plaque in a small neighborhood park. It explains that here was the residence and dental practice of the Unna family, until 1939, or until they were denied access to air raid shelters because they were jewish. A subsequent direct hit on the building killed the entire family. The park is called Unna Park. The written content of the Plaque seems surreal in their surroundings. The park looks nice and peaceful. There's a playground, usually some vendor selling ice cream or hot dogs, and benches full of old people feeding pigeons and seagulls (Pretty sure those winged vermin get 90% of their sustenance from old people)
Now, if we fuse these elements, we get: The Shelter.
A disused subway line in [REDACTED], Germany, consisting of ~48km of tracks and 11 Stations. It was the fist subway line constructed in the city, although since then all records pertaining to it have been seized or destroyed. All non-jewish, non-gypsy German individuals of a heterosexual persuasion (or, more generally, all people Hitler would've been okay with) entering the tunnels or one of the stations will find themselves unable to leave. After realizing that the way they came in will not let them out, they will be compelled to wander the tunnels to look for alternative exits. However, even though the stations and maintenance access doors in the tunnels have functioning electric lights, none of the subjects affected by the Shelter can perceive any light at all. They stumble along the endless tunnels in complete darkness. They cannot perceive any of the exits, and even if directed to an exit it will simply not exist for them. after some time, subjects will perceive auditory hallucinations, growing louder and more severe over time. It starts with hushed whispers and babies crying. Soon after they will be able to hear and feel impacts of aerial bombardment. The whispers become more prevalent, and soon it seems to the subject that they are surrounded by frightened people, all whispering to each other. Sometimes the whispers are interspersed with loud, angry arguments and very rarely gunshots, which echo for many minutes in the tunnels. After exactly 24 hours, subjects, which at this point suffer from great exhaustion and psychological distress, will hear a heated and desperate argument between two individuals about 100m ahead of them. The words of this exchange are the exact same during each experience. I'm too lazy to think of a whole dialogue at this point, but essentially, it's 2 SS officers talking about the hopelessness of their situation, and one of them suggesting he feels bad for the things he's done and saying they deserve no better. After another couple of seconds, 2 gunshots will be heard and the flashes from a handgun's muzzle will be visible to the subject, the only bit of light the subject will have seen since he entered the shelter. When the subject approaches the area and investigates it, he will be able to feel two bodies lying on the tracks, one of them holding a pistol containing exactly 1 more bullet. Neither the bodies nor the weapon exist for anyone not under the Shelter's effects. Psychological distress will be enough in most subjects to use the weapon to commit suicide then and there. If not, the subject will continue exploring the tunnels, but as to date 100% of all subjects have eventually used the gun to end themselves. Neither the gun nor its bullet physically exist, but physical damage to the subject caused by the gun very much does. Subjects report an engravement on the gun's handle: "Der einzige Ausweg", "The only way out."
