Colin says: There are a good number of concrete constructions similar to this both in Barrow and on Walney. They are an assortment of searchligh/gun emplacements and lookouts which were built to as a defence against German attacks during World War Two. Whether the brick construction on the top of this one was a later addition or part of the original design I have no idea - but I wouldn't have liked to be in it if it got hit.
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