From the “Casa dell’Acqua”, today in the Municipality of Volla, which already collected the springs captured by Vesuvius in the Middle Ages, a bubble of water (volla from the Neapolitan bubble) came out through a basin. A stone divider separated the water that arrived in the city in underground pipes, destined for Neapolitan citizens, from the water destined for agricultural land that fed along their path also the mills of numerous farmhouses, until reaching the sea on the southern outskirts of the city.