Lichtenburg was a Nazi concentration camp, housed in a Renaissance castle in Prettin, near Wittenberg in the Province of Saxony. Along with Sachsenburg, it was among the first to be built by the Nazis, and was operated by the SS from 1933 to 1939. It held as many as 2000 male prisoners from 1933 to 1937 and from 1937 to 1939 held female prisoners. It was closed in May 1939, when the Ravensbrück concentration camp for women was opened, which replaced Lichtenburg as the main camp for female prisoners.