The Austrian camp, close to the border with Czechoslovakia, was originally built for troops taking part in military exercises.
There were 40 barracks, 20 each side of a central aisle. The land was bound by two lines of barbed wire, the perimeter illuminated by floodlights.
Escape seemed almost impossible. Almost…. and it is remarkable that we can see it.
Through some extraordinary ingenuity – and cunning – the men filmed their efforts.
Their rarely seen footage is called Sous Le Manteau (Clandestinely). So professional is it that on first viewing you would be forgiven for thinking it is a post-war reconstruction.
It is in fact a 30-minute documentary, shot in secret by the prisoners themselves. Risking death, they recorded it on a secret camera built from parts that were smuggled into the camp in sausages.
The prisoners had discovered that German soldiers would only check food sent in by cutting it down the middle. The parts were hidden in the ends.
The camera they built was concealed in a hollowed-out dictionary from the camp library. The spine of the book opened like a shutter. The 8mm reels on which the film was stored were then nailed into the heels of their makeshift shoes.
It gives an incredible insight into living conditions within the camp. The scant food they were given, the searches conducted without warning by the German soldiers. They filmed it all, even the searches, right under the noses of their guards.