The ruins stand on the site of the ancient city of Poseidonia, founded by greek in the 7th century bc.Posidonia was a Greek colony until  the romans took over the colony in 273 b.C. and posidonia became Pastum: Romans enlarged the settlement and made Paestum more beautiful with an amphitheater and a square.

The best way to explore Paestum by car: with public trasportation you need to take one or two bus and a train..while if you go from Positano to Paestum by car stop in one of some mozzarella factory by the way (like Vannullo or Riva Bianca, very famous hand made factory) to taste a delicious buffalo mozzarella.