The Cave of the Seven Sleepers is a man-made ritual complex in Turkey, near Ephesus, where seven dudes (and a dog, if you prefer the version in the Koran) were entombed alive during the persecutions of Decius. They went to sleep and woke up 200 years later, which is a pretty cool story.
Click on the image for a larger version. I imagine a setup like this: Forbidden catacombs, sealed off by a cruel emperor ages ago. Intrepid explorers expect the restless dead, but when they crack the seal, they wake up a bunch of confused guys speaking an archaic version of the local language and marveling at tempered steel and bullseye lanterns.
