An ancient city of southern Italy southeast of Naples. Founded in the sixth or early fifth century B.C., it was a Roman colony by 80 B.C. and became a prosperous port and resort with many noted villas, temples, theaters, and baths. Pompeii was destroyed by an eruption of Mount Vesuvius in A.D. 79. The incredibly well-preserved ruins were rediscovered in 1748 and have been extensively excavated.