City of Ontario (population 25,920 12.41 km 2) in the Province of Naples, located on the right bank of the river Sarno, just upstream of the outlet in the Bay of Naples at the foot of the southern slope of Vesuvius. The village located in a swampy area until the last century, has developed mainly in the last century in 1883 following the construction of the Shrine of Our Lady of the Rosary for the ardent initiative of Blessed Bartolo Longo. The center was created as an independent town March 29, 1928 Law n.261 including parts of the territories of Scafati, Boscoreale Gragnano and Torre Annunziata. The most recent expansions have led to the almost complete sealing of the center with neighboring clusters Scafati and Torre Annunziata. An important resource for the local economy is made up of tourism attracted by the famous shrine and the remarkable and unique in the world, archaeological and artistic heritage of Pompei. The ancient Pompeii was founded, probably by Osci, later inhabited by the Etruscans, Greeks and Samnites, became a Roman colony in 91 BC. Was completely destroyed by the eruption of Vesuvius on August 24 AD 79. Its discovery was made thanks to the work of excavation undertaken in 1748 by King Charles of Bourbon. The excavations, the finds and the intense debates, hampered the success of Neoclassicism in the 700.