Colditz castle, located in eastern Germany between Leipzig and Dresden, was one of the war's most notorious prisoner-of-war camps. Between 1940 and its liberation in 1945, it held thousands of prisoners, many of them high ranking allied officials. During the war, German authorities often boasted that Colditz was an "escape-proof" POW camp. In 1973, the Parker company even created a board game called 'Escape from Colditz':
Among those imprisoned at Colditz in the winter of 1940 were thirty British officers, lead by Lieutenant Airey Neave. According to Colditz historian Michael Booker, after attempting numerous forms of escape, the officers decided to try tunnelling their way out of the castle.
After nine months of digging, the officers emerged not outside as they had planned, but in the castle's wine cellar, which belonged to the then presiding commander, colonel Gerhard Prawitt. They had read the compass wrong.
According to Booker, the officers proceeded to drink 137 bottles of the colonel's wine, filled them with their urine, placed them back, and escaped back through the tunnel. That works out to about four and a half bottles per person. The escape attempt had clearly made Neave and his men very thirsty.
The story wasn't confirmed until 1974, when Prawitt's widow Elisabeth Prawitt grudgingly confirmed it. However she claimed that the stunt had been pulled not on her husband, but on the colonel that had been in charge of Colditz before him.
For those wondering what eventually happened to the British officers, there is some good news. Lt. Neave became one of the few people to escape Colditz on January 5th, 1942 after he procured a German uniform, climbed through a secret attic passageway the prisoners had found, walked confidently across the grounds of the castle, and made his way to the Swiss border in civilian clothes. He became the first British officer to make a 'home run' (escape successfully) out of the castle.