Castello Aragonese, Ischia, Province of Napoli, Campania, Italy

Probably built on the remains of a garrison of the 5th century AD, that tradition says was originally a garrison of Syracuse dictator Jerone, and from him it was still called in the Middle Ages "Castel Gerone".
Castello Aragonese - Ischia (NA), Campania At that time a small citadel rose around it, with houses and churches. In 1438 Alfonso I of Aragona ordered the 228-meter long bridge to be built in order to connect the island where the castle rose to the land. Under the d'Avalos family the castle rose to great splendor, later historical events caused it to pass to the French, the English and finally the Bourbons, who used it as a prison. Presently it is private property.

More info on the Island of Ischia.