From Wikipedia: Pompeii is a ruined and partially buried Roman city near modern Naples in the Italian region of Campania, in the territory of the comune of Pompei.
It, along with Herculaneum (its sister city), was destroyed, and completely buried, during a catastrophic eruption of the volcano Mount Vesuvius spanning two days on August 24 79 AD.
The volcano collapsed higher roof-lines and buried Pompeii under many meters of ash and pumice, and it was lost for nearly 1700 years before its accidental rediscovery in 1748. Since then, its excavation has provided an extraordinarily detailed insight into the life of a city at the height of the Roman Empire. Today, it is one of the most popular tourist attractions of Italy and a UNESCO World Heritage Site.