Daily Factoid

U-Boat Bases and Bunkers: U-Boat Bunker pen entrances were protected with massive steel shutters that reached up to a meter in thickness or with hollow doors made from thick plate that was then filled with concrete.

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Charles McCain

Charles McCain is a Washington DC based freelance journalist and novelist. He is the author of "An Honorable German," a World War Two naval epic. You can read more of his work on his website: http://charlesmccain.com/

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