Three years before Germany invaded Poland in 1939, Adolf Hitler ordered the construction of the world’s largest tourist resort, located on a beachfront property on the island of Rügen.

The Nazis called it Prora.

Capable of holding more than 20,000 residents, Prora was meant to comfort the weary German worker who toiled away in a factory without respite.

According to historian and tour guide Roger Moorhouse, it was also meant to serve as the carrot to the stick of the Gestapo — a pacifying gesture to get the German people on Hitler’s side.

But then World War II began, and Prora’s construction stalled — until now.