Closed door
Unknown facilities hidden away

 
It is a guess what's behind this wall, but anyhow, it needs fresh air over light. The little sign to the right says "B 1395 35 26", which isn't very helpful too.

 
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Camera: Nikon FM3a, 24mm f/2.8 AI Nikkor.
Film: Ilford FP4 Plus.
Artificial colours added by me.