The elegant 15th-century Ponte Aragonese connects Ischia Ponte to Castello Aragonese, a sprawling, magnificent castle perched high and mighty on a rocky islet. While Syracusan tyrant Gerone I built the site’s first fortress in 474 BC, the bulk of the current structure dates from the 1400s, when King Alfonso of Aragon gave the older Angevin fortress a thorough makeover, building the fortified bastions, current causeway and access ramp cut into the rock.

At the base of the complex you pay the entrance fee and then ascend via a lift or a series of paths that take you on a looping route through the buildings and lush gardens. Further up lie the sunbaked, stuccoed ruins of the 14th-century Cattedrale dell’Assunta, which collapsed under British cannon fire in 1809. The 11th-century crypt below features snippets of 14th-century frescoes inspired by Giotto. Better preserved is the 18th-century Chiesa dell’Immacolata, with its Greek-cross plan and dome studded with curved tympanum windows. Commissioned by the adjoining Convento delle Clarisse (Convent for Clarisse nuns), it was left in its minimalist state after building funds ran out. When the nuns’ own lives expired, they were left to decompose sitting upright on stone chairs in the macabre Cimitero delle Monache Clarisse as a grim reminder of mortality; the now empty chairs remain on view.

Carry on until you reach the elegant, hexagonal Chiesa di San Pietro a Pantaniello and sombre Carcere Borbonico, the one-time prison for leading figures of the Risorgimento (the 19th-century Italian unification movement), such as Poerio, Pironti, Nusco and Settembrini. There's a small and grisly Museo delle Torture, with a collection of medieval torture instruments and impressive armour and weaponry. While you are strolling around, you may want to counteract all that darkness surrounding the bulding’s history with a touch of fairytale romance: in the 1500s, the castle was home to Vittoria Colonna, a poet-princess who married Ferrante d’Avalos here before becoming closely linked with Michelangelo. The great artist wrote romantic poetry dedicated to Vittoria and sent her a painting, the Crucifixion, for her private chapel.

The complex includes a couple of attractive though rather pricey terrace cafes, and a hotel.