The Tränenpalast (Palace of Tears) was the departure hall at Friedrichstraße station for travelers departing from East Germany to West Berlin during much of the Cold War. It now houses an interesting free museum.
Passport controls were very strict with the slightest doubts or mistakes could lead to interrogation, jail and a prohibition on travel. Both German and foreign travelers had to pass through the strict controls. Mirrors allowed the official to check for anything suspicious at the back of travelers. In typical East Germany style, the left ear was considered more revealing of true identity than the face.