The news about the distribution of "Human seats" on the island during the Middle Ages, are extremely fragmentary and incomplete. The Roman Sandstone, whose settlement was greater in the area of Lacco, from the second half of the first millennium AD, called Insula Maior or simply Insula, whose dialect, Island, derives the name Ischia.
Under the threat of barbarian invasions of Saracens first and then, the islanders took refuge on the island said today Castello d'Ischia, within the circle of its heavily armed walls. The circuit of the walls, circular in shape, it is likely that the settlement on the rock has been called "Group" and "Castrum Gironis" the castle on its summit. The decentralization of urban occurred in the Roman Age continued its modest expansion on the island while maintaining the predominantly agricultural nature, as taken from ancient sources on the origins of churches, monasteries and chapels, documents which, although not accompanied by a rigorous clarification of facts topographic , presuppose the existence of settlements of a certain size.
