The deadly gas from the „door of the underworld“

Ruins of ancient Hierapolis, in present-day Turkey. Crédits: Alexei Danichev/ Ria Novosti
Ruins of ancient Hierapolis, in present-day Turkey. Crédits: Alexei Danichev/ Ria Novosti

Toxic carbon dioxide emissions were measured in the Roman temple of Plutonium, god of the underworld, in Hierapolis (Turkey). In ancient times, they had been used to sacrifice animals during mysterious rites.

Hell and radiation! At Hierapolis, near Pamukkale in Turkey, Plutonium, a Roman sanctuary dedicated to Pluton, king of the Underworld, was not paved with good intentions … but rather animal bones! Beasts sacrificed to the most dreaded deities by a mysterious process.

2200 years ago, the faithful people could attend a strange spectacle. When the animals escorted by priests approached the „entrance to the underworld“, a small stone door, the animals died suddenly, without any contact, while the officiants came out unscathed … By what miracle?

The Greek geographer Strabon (65 BC-25 AD) was convinced that the eunuch priests of the local cult of Cybele were protected because they were castrated. But the truth is far more prosaic.

Taking measurements on the former Plutonium site in Hierapolis, Turkey. Credits: Hardy Pfanz
Taking measurements on the former Plutonium site in Hierapolis, Turkey. Credits: Hardy Pfanz

Taking advantage of a rare natural phenomenon, the Romans had actually erected these temples on geological faults releasing carbon dioxide CO2. A concentrated cloud of carbon dioxide asphyxiated everyone who inhaled the gas.

A research team led by volcanologist Hardy Pfanz of the University of Duisburg-Essen, Germany, visited the site of Hierapolis to analyze the deadly potential of the ancient Plutonium discovered in 2011.

In an article published in the journal Archaeological and Anthropological Sciences, scientists explain how, using a portable gas analyzer, they measured the content of gases escaping from the „door of the underworld“. In the Pluto Temple and the small cave below (where very high CO2 concentrations continue to kill birds, insects and small mammals), these geochemical surveys have mostly established that the concentrations of gas supposed to reflect the breath Hadean (of Hades, Greek name of Pluto), evolved during the hours of the day.

In this region of Turkey with very active seismicity, the deep fissure beneath Plutonium continuously emits carbon dioxide in the form of a fog. If during the day, the heat of the solar star dissipates the gases, at night, and at dawn, the CO2 heavier than the air forms a water table floating above the ground, about forty centimeters thickness.

Small current victims of carbon dioxide emissions, near the ancient Plutonium sanctuary of Hieropolis. Credits: Hardy Pfanz
Small current victims of carbon dioxide emissions, near the ancient Plutonium sanctuary of Hieropolis. Credits: Hardy Pfanz

Its density would be enough to kill a human being, according to specialists. „The eunuch priests probably made their sacrifices in the morning or in the evening, when the concentration of gas was the highest,“ say the experts. Thanks to their large size, protecting their noses, or interrupting their breathing for a moment, priests escaped toxic inhalations, unlike animals (including cattle), which were asphyxiated within minutes. A power that the audience was to attribute to the chtonian supernatural powers.

The practice of castration has existed in Europe since ancient times among Greeks and Romans. In the earliest times, it was mainly religious and mystery cults, such as that of the Phrygian goddess Cybele. To enter the service of the goddess, the Corybantes, priests also called „galls“ or „Galli“, practiced self-castration rituals, called sanguinaria.