The demolition of the gas chambers
The first crematorium and gas chamber, and the two “bunkers,” were withdrawn from use in 1943, when the four large crematoria and gas chambers in Birkenau went into operation.
The gas chamber in crematorium I in the Auschwitz main camp was used for the last time in December 1942, although the crematorium furnaces there functioned until July 1943.
The crematorium I building was adapted as an air-raid shelter in 1944. The first provisional gas chamber, bunker 1, was demolished in 1943, while the second, returned to operational use in the spring of 1944, was demolished in the fall of 1944.
As part of the overall liquidation of the evidence of crime, crematoria II and II together with their gas chambers were partially dismantled in late 1944, and blown up in January 1945. Crematorium IV was partially burned during the Sonderkommando mutiny on October 7, 1944, and later dismantled. Crematorium V functioned until the very end, and was blown up on January 26, 1945, the day before the liberation of the camp.