The 1944 escape from the Stalag Luft III camp remains one of the most audacious wartime acts pulled off by Allied officers - even if McQueen's dash for the border was fictional.

And the reality of daily life behind the wire was brought vividly to life in a fund of stories delivered yesterday by two former prisoners, invited to give a talk to airmen and women at a North Yorkshire base.

As moves are made to build a exact replica of the hut that contained the famous Tunnel Harry, on the site of the original prisoner of war camp, near the town of Sagan, now in Poland, 90 Signals Unit at RAF Leeming played host to former bomber crew members Charles Clarke, who helped plan the escape, and Andrew Wiseman.

While they reminisced about Red Cross food parcels and other necessities of life in close confinement, the highlight of a prisoner of war day on the station was a lunch consisting of a typical 1944 menu - corned beef hash and cabbage and potato soup. Mr Clarke, an 84-year-old retired air commodore, was a bomb aimer on a Lancaster when his aircraft was shot down in 1944 during one of many RAF raids on a heavily defended Berlin.

After bailing out, he tried to reach neutral Switzerland, but was captured and ended up in Stalag Luft III.

Mr Wiseman, 85, was born in Berlin to Polish Jewish parents who sent him to England for his education following the rise of Nazism.

He was in a Halifax shot down over France in 1944 and arrived at Stalag Luft III shortly after the historic escape.

The purpose-built camp was opened in 1942 and was considered escape-proof by the Germans, who hoped such attractions as a sports field, a theatre and gardening would discourage anyone from trying to get out.

One who remained defiantly unconvinced was Squadron Leader Roger Bushell, a Spitfire pilot who hatched a plan to spring at least 200 prisoners by tunnelling out. It involved three tunnels named Tom, Dick and Harry, but the first two were discovered by the Germans. The escape through Tunnel Harry below hut 104 was fixed for a moonless night in March 1944, but its exit was on the path of a patrolling perimeter guard and a few feet short of a sheltering wood.

This caused uncertainty about when to give the all-clear and further delays caused by men panicking in the tunnel meant that only 76 managed to escape.

Mr Clarke and Mr Wiseman said this led to a tougher stance against escaping PoWs by the Germans, who had largely been observing the Geneva Convention. Hitler personally ordered 50 of the men to be executed by the Gestapo. Mr Wiseman said: "It ceased to be a game."

Three men made it back to the UK, but 23 were recaptured and returned to Stalag Luft III, where the commandant was court martialled by the Gestapo for failing to prevent the escape.

Mr Clarke and Mr Wiseman described the ingenious methods adopted in digging the tunnel, which had electric lighting and a makeshift rail system, while prisoners played cat and mouse with German guards, known as ferrets because they were looking for anything suspicious. Powdered milk containers became part of the tunnel's air pump.

Talents in the camp were so diverse that the plan involved a network of forgers producing maps and other papers so convincing that they were more up to date than corresponding German documents, while tailors skilfully cut and dyed military uniforms to produce civilian dress.

Powdered milk from food parcels was used for making pancakes, prisoners could receive news from the BBC on a homemade radio that had to be dismantled every day to conceal it from guards, and cigarettes became camp currency.

Education among prisoners was such that the camp became known as a university behind the wire and some men went on to distinguish themselves after the war.

Mr Clarke, who worked behind the scenes on the escape, said: "People who were shot down early in the war settled down better than people like us, because they knew they were going to be there a long time.

"For morale, we had the radio and someone would take the news down in shorthand and go from hut to hut reading it. Morale would be up and down according to how the news went. The favourite expression was we would be home by Christmas - no one said which Christmas."

Mr Wiseman recalled that discipline was good, but said: "Some people could cope better than others. I had no great desire to escape, but some were driven mad by it. After five years my brother-in-law needed psychiatric treatment when he came home."

Mr Clarke said of the film: "It was fairly artificial and Boy Scoutish, and everyone had perfect Oxford accents when 75 per cent of the chaps who were shot down were NCOs, but who would remember the 50 who were murdered without the film? It has been a very emotional experience sharing our memories. We all grew up into men during that period. Eighteen months in a PoW camp is a very long time for a young man."

Yesterday's event was organised with the help of the RAF Ex-Prisoner of War Association. The audience was also told of the infamous Long March of 1945, when thousands of Allied prisoners were forcibly driven westwards in freezing temperatures as the Russian Army approached Germany.

Today, groups are able to follow the same route and use the original barns and warehouses where prisoners, walking without food, water or adequate clothing, found brief shelter.

The project for a replica of Hut 104 as a memorial and an education centre was the idea of Mr Clarke and Howard Tuck, a Cambridge lecturer specialising in the Second World War, and is being supported by 90 Signals Unit. Building is due to start in August, following fundraising throughout the RAF