The entrance to Auschwitz II-Birkenau (left) is the most famous of all camp gates. It was not the only one that instilled terror. Many camps had gatehouses that symbolized a threshold over which prisoners crossed into a living hell. Notes camp expert Wolfgang Sofsky: "The gatehouse was a simple functional structure, architecturally hardly worth an extra glance. Yet as a social locus it was the symbol of camp power, its squat monument."