Parma is a province and town of Emilia-Romagna, a region stretching from San Marino and Ravenna in the east to Piacenza in the west. It lies on the fertile alluvial plains of the Po, just below the foothills of the Appenines. Maize and wheat are grown in the vicinity, the maize being used to fatten the cattle whose milk is turned into the famed Parmesan cheese. The whey is fed to the pigs, whose meat is turned into Parma hams and culatello. Even the chickens do not escape this wonderful cycle of production, being fed on maize to ensure that the whites have the correct consistency for making hard white semolina pasta and the yolks have a rich yellow colour.