The Widerstandnesten (“nests of resistance”) located within the immediate vicinity of the shore, on cliffs, dunes or sea walls, were lighter structures than the coastal batteries. They were intended to provide close defence of the beaches against assault troops.
They generally comprised one or two casemates housing medium-calibre guns (50-, 75- or 88-mm), positioned so as to rake the shore, Tobruks (concrete pits embedded in the ground and fitted with a circular lid where an infantryman could be posted) and mortar, machine-gun and anti-aircraft-gun positions, all connected by a network of trenches.
By the spring of 1944, there were no fewer than 200 Widerstandnesten along the coasts of the Seine Bay. There were, for example around fifteen along the six-kilometre stretch of beach between Vierville and Colleville (future Omaha Beach sector).
These close defences caused far more losses among Allied troops on June 6th 1944 than the coastal batteries.