U-Boat Bases and Bunkers: U-Boat Bunker pen entrance doors did not reach the full length of the opening ending either at the water level or at the quay level (approximately one third of the way above the water level). The water level and below were protected with anti-torpedo nets.
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/ View all posts by Charles McCain