The name of the town is linked to history and legend at the same time. According to tradition, the name derives from the Latin words sinus (gulf) and Petri (Peter) that is Gulf of Peter, alluding to the landing of Saint Peter at Biscione. However, there is not any historical document to validate this theory. The other theory, more popular than the first one, is linked with its distinctive toponym that seems to come from the Greek word Petrosilion then changed in Piddusino by local dialect.
In ancient times, in this uninhabited area grew in abundance a type of aromatic herb known as parsley, due to this vegetative characteristic the place was called Petrosino.
The first settlements, dating back to the mid-seventeenth century, were established by farmers who formed housing units called chianura and by fishermen who settled on the coast forming Biscione village.
The residential area developed from the 19th century along the road where the English merchant John Woodhouse built his “baglio” (rural fortified structure) whose portal later became the coat of arms and the symbol of the town.
The municipal autonomy dates back to 1980 when Petrosino, till then fraction of Marsala, became the youngest town in the province of Trapani.
Petrosino has the highest production of grapes per inhabitant and it significantly contributes to the Marsala wine production. The landscape is characterized by an immense number of catarratto and grillo vineyards.
In addition to agricultural and wine making vocation, Petrosino is also rich in amazing sandy beaches that in summer time are crowded of bathers.