An unfinished AT pillbox
The British Expeditionary Forces had little to build their defenses in the harsh winter of 1939/40, so many pillboxes were not finished when the Blitzkrieg started. This is a pillbox for a 2-pounder AT gun north of Orchies. Only the roof still had to be finished when all the work stopped. It still has all the reinforcement bar sticking out, giving a good idea of their density.