Paestum (ˈpɛstəm , USalsoˈpiːstəm , ˈpae̯stũː) was a major ancient Greek city on the coast of the Tyrrhenian Sea in Magna Graecia. The ruins of Paestum are famous for their three ancient Greek temples in the Doric order dating from about 550 to 450 BC that are in an excellent state of preservation. The city walls and amphitheatre are largely intact, and the bottom of the walls of many other structures remain, as well as paved roads. The site is open to the public, and there is a modern national museum within it, which also contains the finds from the associated Greek site of Foce del Sele.
Solinus wrote that it was established by Dorians. After its foundation by Greek colonists under the name of Poseidonia (Ποσειδωνία), it was eventually conquered by the local Lucanians and later the Romans. The Lucanians renamed it to Paistos and the Romans gave the city its current name. As Pesto or Paestum, the town became a bishopric (now only titular), but it was abandoned in the Early Middle Ages, and left undisturbed and largely forgotten until the eighteenth century.
Today the remains of the city are found in the modern frazione of Paestum, which is part of the comune of Capaccio Paestum in the Province of Salerno in the region of Campania, Italy. The modern settlement, directly to the south of the archaeological site, is a popular seaside resort with long sandy beaches. The Paestum railway station on the Naples-Salerno-Reggio Calabria railway line is directly to the east of the ancient city walls.
Much of the most celebrated features of the site today are the three large temples in the Archaic version of the Greek Doric order, dating from about 550 to 450 BC. All are typical of the period, with massive colonnades having a very pronounced entasis (widening as they go down), and very wide capitals resembling upturned mushrooms. Above the columns, only the second Temple of Hera retains most of its entablature, the other two having only the architrave in place.