A team of NASA engineers aboard the Gulfstream III detected something buried under the ice sheet in Northwestern Greenland. NASA scientists didn't know what it was at first, until discovering it was Camp Century, a Cold War relic built by the United States in the 1950s and abandoned less than a decade later. The 'secret city' became visible via radar. So what is it, and what are the implications?
Curious to know more? Click through the gallery!