Kleine Festung
The Kleine Festung or “Little Fortress” was a prison in Theresienstadt and contained all the non-Jewish prisoners. Ironically, mail from the Kleine Festung received the Theresienstadt cancellation, by mail from the ghetto did not.
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This postcard that was mailed from the Kleine Festung has a circular Theresienstadt cancel dated January 5, 1942. The third line in the return address indicates that the card is from the Kleine Festung.