Lager Helgoland
It was organised by the Schutzstaffel - SS-Baubrigade I–which was first under supervision of the Sachsenhausen concentration camp near Berlin; and from mid-February 1943 under the Neuengamme camp in northern Germany. It was used by the Nazi Organisation Todt forced labour programme, to build bunkers, gun emplacements, air-raid shelters, and concrete fortifications.