Love these posts. Keep it up.
I was at Cologne Cathedral a couple of months ago. It is basically a mammoth, man made, cavern of stone.
The cathedral, being very near to the central railway station, suffered fourteen hits by aerial bombs during World War II. It did not collapse, but remained standing in an otherwise flattened city. The great twin spires are said to have been used as an easily recognizable navigational landmark by Allied aircraft raiding deeper into Germany in the later years of the war, which may be a reason that the cathedral was not destroyed.