Topf and Sons

J.A. Topf and Sons was an engineering company, founded in 1878 in Erfurt, Germany by Johannes Andreas Topf . Originally, it made heating systems and brewing and malting equipment. Later, the company diversified into silos, chimneys, incinerators for burning municipal waste, and crematoria. During World War I it made weapons shells, limbers and other military vehicles. In World War II it also made weapons shells and aircraft parts for the Luftwaffe.
It is now infamous as the largest of 12 companies that designed and built crematoria ovens for concentration and extermination camps during the Holocaust, planned and carried out by the Nazi regime from 1935 to 1945. The company not only made crematoria ovens, it also made ventilation systems for the gas chambers at Auschwitz II–Birkenau.

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