Ancient Chamber Fed by Deathly Fumes

Sept. 19, 2006 — A secret tunnel linked an ancient Temple of Apollo in western Turkey to a death chamber that to this day is still full of naturally occurring poisonous gas, according to a study published in the November Journal of Archaeological Science.

The discovery adds to the growing body of evidence that many early Greek and Roman temples were built on or near sites of geological activity that produced "special effects" to awestruck onlookers. In this case, visitors in ancient times must have viewed sacrificial spectacles that probably then seemed like magic.

According to the study and descriptions by early writers, such as the Greek geographer Strabo (64 B.C.- 24 A.D.), rituals would have centered around the underground death chamber at the temple, called the Plutonion.

Prior research determined that geothermal activity releases high concentrations of poisonous carbon dioxide gas in its underground cavity.

"The Plutonion was used in the past to perform animal sacrifices and only the eunuchs (castrated males) of the Temple of Cybele (an ancient cult) were able to spend time within the cavern without being affected," said co-author Giovanni Leucci of the University of Lecce-Via Arnesano in Italy.

"This was possible because the eunuchs covered their heads with probably four sacks of cloth," added Leucci, who conducted the study with his colleague, Sergio Negri. "Inside the sacks a pocket of air formed that allowed the eunuchs to remain for a few minutes inside the Plutonion without being affected."

Leucci explained that this "death chamber" looks like a 30-foot-wide hole. A thick mist of gas pours out of the hole, which, he said, "makes it impossible to see inside" and complicates excavation work.

To safely investigate the chamber and the nearby 100 B.C.- 3rd century A.D. Temple of Apollo, Leucci and his colleague used ground penetrating radar and electrical resistivity tomography, both of which locate and measure possible underground structures.

Approximately 8 to 14 feet below the temple, they found a tunnel leading to the death chamber. They also discovered a room, measuring approximately 13 feet across, at the same depth under the temple.

"This structure could have been used to prepare the sacrifices," Leucci said. "Any living creature that would have entered the hole (without some protection) would have died instantly."

The researchers now think other temples dedicated to Apollo — a Greek god of prophesy, healing, light, poetry and music — were intentionally built over active geothermal springs. These include temples at Didyma and Claros in Turkey, which was once part of the Greek and Roman empires.

According to ancient texts, the temple at Didyma used to house an oracle that likely performed rituals at the site’s "sacred spring." It's also now believed the famous Oracle at Delphi may also have achieved "visions" thanks to the effects of gaseous venting. Researchers suspect she inhaled ethylene gas, the same gas used today to ripen certain fruits and vegetables.

Maria Teresa Carrozzo, professor of applied geophysics at the University of Lecce, told Discovery News that she thinks the new study is "very interesting" and validates scientific speculation that the Temple of Apollo was linked to the Plutonion.

However, she added, "The presence of such (underground) structures can only be definitively confirmed by excavation."