bicyclecards.com

d8Lwj TIL During World War II, The United States Playing Card Company created a very special deck of cards known as the “Map Deck.” When soaked in water, these decks could be peeled apart to reveal hidden maps that allowed escaping prisoners to find their way to safety.
E1rvV TIL that the Bicycle playing card company made decks of cards and gave them to the prisoners of war in Germany with hidden escape routes revealed when the cards were soaked in water as Christmas presents.
Oo6pe TIL Bicycle Playing Card Company joined forces with American and British intelligence agencies to create a special deck of cards, specifically created to help allied prisoners of war escape from German POW camps.