There, the local population were far more reluctant to help the Germans. Indeed, most labour had to be brought in.[2] The ground selected for bunker construction was no help either: usually being at the head of a fjord, the foundations and footings had to be hewn out of granite. Several metres of silt also had to be overcome.[3] Many of the workers needed were forced labour, most especially the concentration camp inmates supplied by the Schutzstaffel from camps near the pens.