The Swabian Castle is a majestic fortress a few steps away from the Adriatic sea. Probably built in 1090 AD on a pre-existing Norman castle, the castle went through several transformations following the ruling dynasties style. Its current square-shaped structure with the four angled bastions at the vertexes, dates back to the Renaissance. After the Norman period, Fredrick II ( 12th cent.), dwelled in the castle and transformed it into a palace. In 1269, during the Angevin Period, Charles I commissioned renovation works complemented by the architect Pierre D’Angicourt. Specifically, the palace and the royal sections. A moat was excavated around the castle together with a westerly external wall, to improve the defensive system. Afterwards, the Aragon Crown fortified the castle to a greater extent. In addition, the Spanish Crown built the small fort of Paraticchio, alongside the coast road. However, it was not enough to prevent the French occupation in 1528. During the Hapsburgs domination, Charles V and the architect Evangelista Menga began important changes, such as ticker walls, that converted the fortress into its current square-shaped structure with the four angled bastions. Although these arrangements were made, the castle was never used for military purposes. At the time of Charles VI Kingdom, the castle was completely abandoned and unusable. It was only in 1813, following Gioacchino Murat‘s visit, under the French protectorate, that the defensive structure strengthening was initiated. In 1876, declared unusable for military purpose, it was sold at auction to the town of Barletta. During the War World I, on May 24, 1915 an event of noteworthy relevance occurred: Six cannon balls hit the castle in the bastion and the north façade. The attack ended with the destroyer arrival. Today it is possible to see the signs of the battle both on the bastion San Vincenzo and on the southern façade, where a commemorative stone has been placed.