Natzweiler-Struthof was a Nazi concentration camp located in the Vosges Mountains close to the villages of Natzweiler and Struthof in the Gau Baden-Alsace of Germany, on territory annexed from France on a de facto basis in 1940. It operated from 21 May 1941 to September 1944, and was the only concentration camp established by the Germans in the territory of pre-war France. The camp was located in a heavily-forested and isolated area at an elevation of 800 metres (2,600 ft).

From 1933 to 1945, Nazi Germany operated more than a thousand concentration camps, including subcamps on its own territory and in parts of German-occupied Europe.