Ploutonion

A ploutonion (Ancient Greek: Πλουτώνιον, lit. "Place of Pluto") or plutonium (from the Latin) is a sanctuary specially dedicated to the ancient Greek and Roman god Pluto (better known as Hades ). Only a few such shrines are known from classical sources, usually at locations that produce poisonous emissions and were considered to represent an entrance to the underworld.

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