Stutthof was a Nazi concentration camp established by Nazi Germany in a secluded, marshy, and wooded area near the village of Stutthof 34 km (21 mi) east of the city of Danzig (Gdańsk) in the territory of the German-annexed Free City of Danzig. The camp was set up around existing structures after the invasion of Poland in World War II and initially used for the imprisonment of Polish leaders and intelligentsia. The actual barracks were built the following year by prisoners. Most of the infrastructure of the concentration camp was either destroyed or dismantled shortly after the war. In 1962, the former concentration camp with its remaining structures, was turned into a memorial museum.