Early 2000's, Mercedes used to have (might still do, don't know) a data center near Munich that was housed in a former Nazi bunker. The Allies blew up most bunk

Early 2000's, Mercedes used to have (might still do, don't know) a data center near Munich that was housed in a former Nazi bunker. The Allies blew up most bunkers at the end of the war but they calculated that the walls on this one were so thick that blowing it up would cause damage over a 5 km radius (I was told). You had to go through a double door that fully fit within such a wall, 2m+ of reinforced concrete. Mighty impressive.