At some point, Sachenhausen, to use a horrible phrase, "upgraded" from a labor camp, where people simply died from disease, overwork or a combination of the two, to a camp where people were routinely exterminated with a good deal of efficiency. Several methods were used to kill people including one utterly hideous one of pretending to measure people's height whilst actually lining the victim up to be shot from behind through the back of the neck. The shooter was concealed in a room behind the false measuring device - I guess the only positive point would be that the victim would be unaware what was about to happen. Otherwise people were herded into this pit, where they were just shot. The wood lined pit was used to contain the people and to muffle any sound from the rest of the camp. The pretence that this section of the camp was a medical facility was curiously maintained for most of its existence (hence the desire to muffle the sound), although, it seems, most inmates were in reality only too aware of their potential fate. Other victims were gassed in chambers adjacent to this site using the common zyklon b method. Total victims of all causes and methods are estimated (per Wiki) at 100,000.