Danevirke
The Danevirke or Danework (modern Danish spelling: Dannevirke; in Old Norse: Danavirki, in German: Danewerk, literally meaning earthwork of the Danes) is a system of Danish fortifications in Schleswig-Holstein, Germany. This historically important linear defensive earthwork across the neck of the Cimbrian peninsula was initiated by the Danes in the Nordic Iron Age about AD 650.