With more than 50.000 m2 (some 10 km tunnnel length) one of the biggest german underground
installations that reached production status in late 1944. According to Allied intelligence reports,
it was "one of the most modern and most complete underground plants in Germany".
Constructed within 13 months by prisoners of the KL Gusen II concentration camp within the
Mauthausen-Gusen complex due to its high mortality (up to 98%), it became one of the most horrible
concentration camp sites in European history (average survival period 4 months).
Main deportations came form KL Auschwitz B and western Europe (France, Italy, Belgium, Luxembourg)
when Nazi-troops had to move out this countries due to military pressure of the Allied Forces.
A vast number of the Jewish man were exterminated by hardest labor at the tunnel construction site.
With Winter 1944/45 more deportations came in than lives were consumed, by construction
and production. So, many died in unopend railway cars at the local station, froze to death or were killed
by the many other cruelties of the KL Gusen II "extermination" camp.
One of the many unknown victims of the KL Gusen II - BERGKRISTALL plant had been the young french
youth activist Marcel Callo. He became beatified by Pope John Paul II. in 1987.
According to Allied Intelligence, some 987 jet propelled planes left serial production lines.
Construction of tunnel-system was nearly finished and installations operational for some 85%.
Production started in parallel to construction of the tunnel-system in Summer 1944 and reached
maximum in April 1945 (some 90 jet-plane fuselages, fully equipped per month).
Original planned production capacity should have been 1.250 jet-planes per month until the year 1955.
Fuselages and wings were brought by railway cars during the night from BERGKRISTALL to several locations
in southern Germany and Bohemia where the turbines had been fixed and the jets became operational.
Secrecy was extremely high: The test-pilots didn't know where the planes came from.
German civilians being employed at BERGKRISTALL were not allowed to give the name of town where they
did work to any third persons.
With the end of the war plans and preparations were made to blast-off this top secret installation
along with the slave-workers, the local population and the other eye-witnesses to prevent knowhow-transfer
to allied forces and to kill potential prosecutors for later Mauthausen-Gusen trials.
This plan was not carried out due to the unclear situation in early May 1945.
Vice-major Aschenbrenner of St. Georgen/Gusen and the Swiss Red-Cross delegate Louis Haefliger played key roles
in an attempt to prevent this tragedy. The installations of strategic importance were later on investigated
and partly dismantled by US troops.
With August 1945 BERGKRISTALL was handed over to the Soviets.
The Soviets dismantled all of the residual installations and finally destroyed the key-parts of this
strategic tunnel-system in November 1947.
After this, BERGKRISTALL and KL Gusen complex became totally forgotten and never appeared in any
scientific- or research thesis.