Aragonese Castle built
1442 CE.
Shown on the map at 40.732°, 13.965°.
Aragonese Castle (Italian: Castello Aragonese) is a castle built on a small tidal island east of Ischia (one of the Phlegraean Islands), at the northern end of the Gulf of Naples, Italy. The castle stands on a volcanic rocky islet that connects to the larger island of Ischia by a causeway (Ponte Aragonese).
Text from the Wikipedia article Aragonese Castle, licensed CC BY-SA 4.0.