"Bergkristall" St. Georgen

This very large plant produced jet-powered Messerschmitt Me 262 fighters. Complete aircraft (without wings) were made on a kind of ‘assembly line’, with production starting in late March 1944. 987 aircraft were manufactured until 1 May 1945. 

All tunnels had been excavated by the end of March 1945 and lined with concrete. Aeroplanes were produced during the war, but production had ceased by 6 July 1945, and parts of the facility had already been removed. 

The tunnel system decayed for decades, until 2001 when the Republic of Austria began with extensive security measures. About a quarter of the plant could be secured by the Bundesimmobiliengesellschaft. Extensive preparation work is required for a visit, which is why this is only possible on a few days a year.