City 40

The Soviet Union was always secretive, but during the Cold War the outside world got hardly any information on what was going on behind the Iron Curtain. Only after the USSR collapsed in 1991 did we learn about the particulars of the Soviet nuclear program, including entire cities that were forbidden territory and kept classified even from their near neighbors. Sure, most of the US didn't know what was going on in Oak Ridge or Los Alamos during World War, but that was temporary. The Americans working in those places knew it wasn't going to be a life sentence. City 40, on the other hand, was like a high-class, luxurious prison for nuclear scientists, technicians, and their families. Weird things happened in City 40, including a nuclear disaster and a story of alien adoption during those secret years. Now known as Ozersk, the city is clearly identified on Russian maps made after the Soviet Union dissolved. (via Digg)