Secret to the Roman 'gate to hell' revealed: Scientists claim the temple doorway belched noxious gas at low heights to kill sacrificial animals but leave priests unharmed The city of Hierapolis in modern-day Turkey was built on geologically active site A 'gate to hell' channelled underground emissions of CO2 into a religious arena Experts measured levels of the gas and discovered something surprising Concentrations of CO2 at head height for animals would have been deadly Thanks to their larger stature their human handlers would escaped unharmed
Mena: people in the Ancient World had sophisticated killing weapons like biological weapon and Biological weapon. I think the Roman priests of the gate to hell temple in Turkey had gas mask thats probably why the toxic gas at the temple killed the sacrificial animals not the priests. i think the gas being under knees level and above knees level is not the reason the Roman priest were not killy by the toxic gas.
Roman priests who survived religious journeys through a deadly 'gate to hell' may have had a helping hand from their height, new research has found. This image shows a digital reconstruction of the site, which was discovered by a team of archaeologists from Italy in 2013
Researchers at the University of Duisburg-Essen in Germany measured carbon dioxide (CO2) concentrations in the arena of the ancient city of Hierapolis. This image shows the site as it appears today
Experts found that levels of the potentially deadly gas contained in these vapours were lower during the day, when the sun's rays would cause them to dissipate. This 3D reconstruction of the Plutonium at Hierapolis shows the The Gate to Hell in the rear wall, below the stone seating
posted 
