The original Auschwitz camp (Auschwitz I) consisted of just 22 basic brick barracks. The camp grew over time and at its peak in summer 1944, it covered about 40 square kilometres in the main area.
It is apparent that during its five years in service, the camp went through much change and alteration. The initial plan in 1940 was to establish a quarantine holding camp, but this was never realised. It became a concentration camp where it is said that prisoners were annihilated by depriving them of the basic necessities of life and then became an immediate killing camp along the lines of Dachau and Treblinka.
From the early days until 1942 it functioned exclusively as a concentration camp. The result was a process of deliberate slow killing caused by inhuman conditions and starvation. During the period from 1942 to October 1944, it continued as a concentration camp for various ethnic backgrounds, whilst being used as the largest immediate mass killing centre for Jews.
In the last two months of its existence after the closing of the gas chambers in October 1944 ahead of the expected Soviet offensive and liberation, the camp entered the phase of final liquidation, which ended with the evacuation of the remaining living prisoners.
The difficulties in running such a large camp complex led to its formal division in November 1943 and the birth of additional facilities in the nearby area. In August 1944, Auschwitz I housed sixteen thousand prisoners. It was also home to the SS garrison administration (SS Standortverwaltung), the commander of the local garrison, and the commandant of Auschwitz I. Also on this site were the main supply stores, workshops, and several SS companies. Work in these enterprises was the main duty for prisoners in Auschwitz I.