Castello Aragonese

The Castello Aragonese is a fortification in Taranto, Italy. Officially called the Castel San Angelo, it was built on the site of older fortifications dating to Greek occupation in the third and fourth centuries BC. In 1481 the low ground in front of the fortification site was excavated to allow the passage of boats, and to create a moated defensive position. The present fortress was built for the then-king of Naples, Ferdinand II of Aragon in 1496 to reinforce the naturally low-lying link between the old town of Taranto on a peninsula, and the mainland.

Source: Wikipedia