The Steinwache — literally "stone watch" — is a former police detention centre adjacent to the main railway station, now preserved as a permanent memorial and museum to the victims of Nazi persecution in Dortmund. The building held political prisoners, Jews, Sinti and Roma, and Soviet forced labourers during the Third Reich; many were interrogated under torture here before being transported to concentration camps.
The permanent exhibition occupies the original cell block and documents Dortmund under National Socialism through individual life stories and historical material. The focus on named individuals — resisters, deportees, victims — gives the history a human weight that abstract statistics cannot. The exhibition is in German with a printed English guide available. Admission is free. The Steinwache is one of the most sobering and worthwhile stops in the city.