Feuerstein Castle

Burg Feuerstein was built in 1941 by Professor Oskar Vierling and served as a secret laboratory for high-frequency technology and electroacoustics until 1945. Around 250 employees conducted research here on behalf of the German war effort, focusing on weapons and communication technology, including speech encryption, acoustic torpedo guidance, and anti-detection technology for submarines. The castle-like architecture not only blended into the Franconian Switzerland landscape but also served as camouflage for a supposed medical facility. After being confiscated by American soldiers at the end of the war, the Archdiocese of Bamberg leased the complex in 1946 and acquired it in 1949.