Australian Paul Royle, one of only two men alive from World War II's daring "Great Escape", says he still has vivid memories of the audacious prison breakout on its 70th anniversary.

Royle, 100, was one of 76 men who tunnelled out of German prison camp Stalag Luft III on a bitterly cold night in March 1944, an event immortalised in the 1960s film "The Great Escape" starring Steve McQueen and Richard Attenborough.

They dug three tunnels -- codenamed Tom, Dick and Harry -- although only Harry was used.

Only three made it to safety from a camp the Nazis said was escape-proof. The rest were captured by the Gestapo and 50 of them executed on Hitler's orders.

Perth man Royle was spared and the former RAF Flight Lieutenant told the Australian Broadcasting Corporation (ABC) he still has vivid memories of emerging from the tunnel to a snowy landscape.

"It was very pleasant and all we saw was great heaps of snow and pine trees. There was snow everywhere, it was cold," he said, maintaining that he was not scared during the dash to freedom.

"You had other thoughts in your mind you see, you wanted to get out," he said.

After making it through the tunnel, Royle waited for his companion and the pair walked through the night before finding a place to sleep for the day in the bushes.

Their freedom was short-lived with the two men recaptured in a small village nearby and taken to a local jail.

Royle was returned to the original camp, ABC said, where he met Australian fighter pilot and writer Paul Brickhill, whose book "The Great Escape" told the story of the mass breakout.

Six hundred people were involved in preparing the tunnels over several months with Royle tasked with disposing of the soil, pouring it into his longjohns, then releasing it in the prison yard when guards were not watching.

"You'd have to be very careful because the soil from the tunnel was a different colour from the soil on the surface mostly, and you would (need to) get a suitable place to put it where there was similar soil," he said.

In the film screenwriters focused on the roles of American POWs, with McQueen making a bid for freedom on a motorbike once through the tunnel, but the real escape was by British and other allied personnel, none being American.

"The movie I disliked intensely because there were no motorbikes... and the Americans weren't there," Royle said, while playing down the significance of the escape.

"Oh I don't think so," he said when asked if what he did was extraordinary.

"Most people have extraordinary lives if they think of it.

"While we all hoped for the future we were lucky to get the future. We eventually defeated the Germans and that was that."

On Tuesday, 50 British airmen began a long trek in Poland to the site of Stalag Luft III to mark 70 years since "The Great Escape".

They are headed to a military cemetery in Poznan, western Poland, where many of the British servicemen who perished in the escape were laid to rest.

The only other living survivor is 94-year-old British man Dick Churchill.