In Kurt Vonnegut's book Slaughterhouse-Five, or The Children's Crusade: A Duty-Dance with Death, the main character Billy Pilgrim is captured by the Germans and taken to Dresden. In Dresden, Billy is held in an unused slaughterhouse, "Slaughterhouse number 5." From this location Billy as well as his captors survive the bombing of Dresden, which killed some 25,000 people in the ensuing firestorm.
This fictional account almost perfectly mirrors Vonnegut's real experience in the war. In WWII Vonnegut was imprisoned in Dresden, was beaten, and made a prisoner in Schlachthof Fünf or Slaughterhouse Five, a real slaughterhouse in Dresden. When Vonnegut emerged from the slaughterhouse he saw what "looked like the surface of the moon" the result of the massive Dresden bombing by the allied forces. In Vonneguts words "There were too many corpses to bury. So instead the Germans sent in troops with flamethrowers. All these civilians' remains were burned to ashes." It would be these horrific experiences that inspired Vonnegut's 1969 book, named after the place that likely saved his life.
Curiously most residents of Dresden couldn't tell you who Kurt Vonnegut was, let alone where the actual Slaughterhouse Five is. It is, in fact right under their feet. Amazingly the Slaughterhouse Five complex is largely intact and is now protected. Recently it has become possible to visit it with a guided tour. The tour takes about 2 hours, and is still a relatively unknown tourist site in Dresden.