This image of London-/Derry in days-gone-by is on the outside of the walls of Derry, looking in. The brickwork of which it appears to be the portal is also fake; in fact, this is a covered walkway leading from Bishop Street to the Fountain.
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Copyright © 2016 Extramural Activity
Camera Settings: f13, 1/320, ISO 400, full size 2592 x 3888