Hades wasn't the happiest place, the Department of Motor Vehicles of the ancient Greek afterlife.

There, in a gloomy underworld, departed heroes such as Achilles gathered mostly to grouse about their boredom, and await the verdict of the judges of the dead.

"I would rather be a paid servant in a poor man's house and be above ground than king of kings among the dead," said Achilles, the greatest of Greek heroes, commenting on the scenery, according to the ancient poem, The Odyssey. (Tough break for Achilles, but perhaps he was later cheered to learn that Brad Pitt would play him in the 2004 film Troy.)

But for archaeologists, a Greek cave that has sparked comparisons to Hades looks more like heaven. Overlooking a quiet Greek bay, Alepotrypa Cave contains the remains of a Stone Age village, burials, a lake and an amphitheater-sized final chamber that saw blazing rituals take place more than 5,000 years ago. All of it was sealed from the world until modern times, and scholars are only now reporting what lies within....