The region of Pompeii was first occupied by the 6th century BC, but it reached its heyday when the Romans turned it into a resort town beginning 81 BC. ompeii's known buildings--and there are many that were preserved under the mud and ashfall--include a Roman basilica, built ca 130-120 BC, and an ampitheatre built circa 80 BC.
One of the most famous archaeological sites in the world, Pompeii and its populace was preserved forever for us in the ash fall, and excavated in the early 18th century by the Royal House of Bourbon.
If you've a taste for more, a whole lot more information about Pompeii can be found in Pompeii, Buried in Ashes.
SourceStorey, Glenn R. 1999 Archaeology and Roman society: Integrating textual and archaeological data. Journal of Archaeological Research 7(3):203-248.
This glossary entry is part of the Dictionary of Archaeology.