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The Zoroastrian Ateshgah “Fire Temple” near Baku, Azerbaijan. The temple was built over natural burning vents which no longer provide gas, and so the flame is now artificially fed via a pipe.

Eternal Flames: Geologists Investigate Ancient Myths to Know More about Modern Fuel

Millennia ago, ancient cultures were astounded by the seeming miracle of natural flames which burned day and night for weeks, decades, or even centuries. The tales of such flames have become a focus...