Here is a little factoid that may be of interest, my mates grandfather was an officer in the RE, he arrived in France and was sent to calais to look at a German bunker/weapon site that no one could quite identify. Well he went and found a whole load of pipes, they had no clue as to what it could be and reported something about drainage with a footnote that it could be a weapon. Apparently he has a photograph of him standing on a load of the segments after some of them had been dismantled.
Just a little thing you may be interested in.

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There's no honorable way to kill, no gentle way to destroy. There is nothing good in war. Except its ending.