This is the larger opening in the back wall. The wall behind the opening slopes up steeply, but is blocked not far up.
Q. What was this used for? Could this have been where the shells would be lifted up to the emplacement above?
(Also if your eyesight is good you'll see a black blob above the left shutter. It was a sleeping bat - the only one we saw in here.)
Date picture taken
unknown
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