https://en.wikipedia.org/wiki/Stalag_Luft_III#The_%22Great_Escape%22_(1944)

Background
In March 1943, Royal Air Force Squadron Leader Roger Bushell conceived a plan for a mass escape from the North Compound, which took place on the night of 24/25 March 1944. He was being held with the other British and Commonwealth airmen and he was in command of the Escape Committee that managed all escape opportunities from the north compound. Falling back on his legal background to represent his scheme, Bushell called a meeting of the Escape Committee to advocate for his plan.

"Everyone here in this room is living on borrowed time. By rights we should all be dead! The only reason that God allowed us this extra ration of life is so we can make life hell for the Hun ... In North Compound we are concentrating our efforts on completing and escaping through one master tunnel. No private-enterprise tunnels allowed. Three bloody deep, bloody long tunnels will be dug – Tom, Dick and Harry. One will succeed!"

Herbert Massey, as senior British officer, authorised the escape attempt which would have good chance of success; in fact, the simultaneous digging of three tunnels would become an advantage if any one of them was discovered, because the guards would scarcely imagine that another two were well underway. The most radical aspect of the plan was not the scale of the construction, but the number of men intended to pass through the tunnels. While previous attempts had involved up to 20 men, in this case Bushell was proposing to get over 200 out, all wearing civilian clothes and some with forged papers and escape equipment. As this escape attempt was unprecedented in size, it would require unparalleled organisation; as the mastermind of the Great Escape, Roger Bushell inherited the codename of "Big X". More than 600 prisoners were involved in the construction of the tunnels.

The tunnels
Three tunnels, Tom, Dick, and Harry were dug for the escape. The operation was so secretive that everyone was to refer to each tunnel by its name. Bushell took this so seriously that he threatened to court-martial anyone who even uttered the word "tunnel".

Tom began in a darkened corner next to a stove chimney in hut 123 and extended west into the forest. It was found by the Germans and dynamited.

Dick's entrance was hidden in a drain sump in the washroom of hut 122 and had the most secure trap door. It was to go in the same direction as Tom and the prisoners decided that the hut would not be a suspected tunnel site as it was further from the wire than the others. Dick was abandoned for escape purposes because the area where it would have surfaced was cleared for camp expansion. Dick was used to store soil and supplies and as a workshop.

Harry, which began in hut 104, went under the Vorlager (which contained the German administration area), sick hut and the isolation cells to emerge at the woods on the northern edge of the camp. The entrance to "Harry" was hidden under a stove. Ultimately used for the escape, it was discovered as the escape was in progress with only seventy-six of the planned two hundred twenty prisoners free. The Germans filled it with sewage and sand and sealed it with cement.



After the escape, the prisoners started digging another tunnel called George, but this was abandoned when the camp was evacuated.

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Murders of escapees
Nationalities of the 50 executed prisoners


Following the escape, the Germans made an inventory of the camp and uncovered how extensive the operation had been. Four thousand bed boards had gone missing, as well as 90 complete double bunk beds, 635 mattresses, 192 bed covers, 161 pillow cases, 52 twenty-man tables, 10 single tables, 34 chairs, 76 benches, 1,212 bed bolsters, 1,370 beading battens, 1219 knives, 478 spoons, 582 forks, 69 lamps, 246 water cans, 30 shovels, 300 m (1,000 ft) of electric wire, 180 m (600 ft) of rope, and 3424 towels. 1,700 blankets had been used, along with more than 1,400 Klim cans.[20] Electric cable had been stolen after being left unattended by German workers; because they had not reported the theft, they were executed by the Gestapo. Thereafter each bed was supplied with only nine bed boards, which were counted regularly by the guards.

Of 76 escapees, 73 were captured. Adolf Hitler initially wanted every recaptured officer to be shot. Hermann Göring, Field Marshal Keitel, Major-General Westhoff and Major-General Hans von Graevenitz (inspector in charge of war prisoners) pointed out to Hitler that a massacre might bring about reprisals to German pilots in Allied hands. Hitler agreed, but insisted "more than half" were to be shot, eventually ordering SS head Himmler to execute more than half of the escapees. Himmler passed the selection on to General Arthur Nebe, and fifty were executed singly or in pairs. Roger Bushell, the leader of the escape, was shot by Gestapo official Emil Schulz just outside Saarbrücken, Germany. Bob Nelson is said to have been spared by the Gestapo because they may have believed he was related to his namesake Admiral Nelson. His friend Dick Churchill was probably spared because of his surname, shared with the British Prime Minister. Seventeen were returned to Stalag Luft III, two were sent to Colditz Castle, and four were sent to Sachsenhausen concentration camp, where one quipped "the only way out of here is up the chimney." They managed to tunnel out and escape three months later, although they were recaptured and returned; two were subsequently sent to Oflag IV-C Colditz.

There were three successful escapees:

Per Bergsland, Norwegian pilot of No. 332 Squadron RAF, escapee #44
Jens Müller, Norwegian pilot of No. 331 Squadron RAF, escapee #43
Bram van der Stok, Dutch pilot of No. 41 Squadron RAF, escapee #18

Bergsland and Müller escaped together, and made it to neutral Sweden by train and boat with the help of friendly Swedish sailors. Van der Stok, granted one of the first slots by the Escape Committee due to his language and escape skills, travelled through much of occupied Europe with the help of the French Resistance before finding safety at a British consulate in Spain.

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