Feuerstein Castle

Feuerstein Castle (German: Burg Feuerstein) lies at the edge of the so-called Lange Meile near Ebermannstadt in the county of Forchheim in the south German state of Bavaria. It was built in 1941 by Oskar Vierling as a laboratory for researching High Frequency technology and electroacoustics and was used until 1945 by 250 employees for research into weapons and communication technology as part of the German armaments programme during the Second World War.

At the end of the war the castle was seized by American soldiers, from 1946 it was rented by the Archdiocese of Bamberg under Jupp Schneider and sold in 1949. Since then the castle and the entire estate have been in use as a Roman Catholic youth and conference centre.

Oskar Vierling was looking for a central location for his laboratories. The choice fell on a hill called the Feuerstein. Its design as a castle blended well into the countryside of Franconian Switzerland and was chosen for camouflage reasons. During the war it was disguised as a hospital and had tiles in the form of a red cross on the roof, but actually housed a laboratory for secret Nazi armament projects. After the end of the war it was abandoned and construction plans and documents were destroyed. Nevertheless, in 2011 a document came into the hands of cryptographer-historian, Norbert Ryska, from the American special unit, Ticom (Target Intelligence Committee), which described the work of Vierling at Feuerstein Castle in more detail. According to this, Vierling worked for the Nazis on speech encoding methods, acoustic torpedo control, acoustic detonation of mines, anti-detection technology for U boats and in the fields of radio and electrotechnology.

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