The deadly vapors that waft out of this "gate to hell" were once used in ancient rituals honoring Pluto, god of the underworld —and still claim the lives of unfortunate birds who get too close.
The Pluto's Gate site, or Ploutonion in Greek, was built on top of a cave that emits toxic gases. Consisting of a temple, a pool, and a cavern—the "gate"—it was seen as a passage to the underworld and formed part of the ruined ancient city of Hierapolis, founded around 190 BC.
Italian archeologists discovered Pluto's Gate in 2013 by reconstructing the route of a thermal spring. During excavations, several birds dropped dead after flying too close to the poisonous emissions. Their deaths echoed the dramatic events that once took place at the Ploutonion.
Two millennia ago, visitors to Pluto's Gate could buy small birds or other animals (the sale of which supported the temple) and test out the toxic air that blew out of the mysterious cavern. Only the priests, high and hallucinating on the fumes, could stand on the steps by the opening to hell. They would sometimes lead sacrificial bulls inside, later pulling out their dead bodies in front of an awed crowd.
As the Greek geographer, philosopher, and prolific traveler Strabo, who lived from 64/63 B.C. to 24 A.D., so enticingly described it: "This space is full of a vapor so misty and dense that one can scarcely see the ground. Any animal that passes inside meets instant death. I threw in sparrows and they immediately breathed their last and fell."
Portals to hell:
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