Fortezza di Gradisca d'Isonzo
Although a locality by the same name had been mentioned in a document dated 1150, the fortified town of Gradisca was built in the late 15th century to defend the Venetian Republic from incursions by the Turks. The town has a roughly pentagonal shape with two gates and a round tower on each corner, and is encircled by a deep moat. Gradisca was posed with another serious threat when Austria inherited the nearby County of Gorizia in 1500. Besieged by the League of Cambrai, pounded by cannon-fire and isolated from the remaining Venetian troops, its population decimated by the plague, Gradisca eventually surrendered in 1511. Since then it remained a possession of the Austrian Empire, which reinforced the town defences and later built a new castle inside its walls. In 1615-1617 Gradisca was at the centre of the so-called “Gradiscan war” between Austria and Venice. Thirty years later, it was acquired by the Prince of Eggenberg. When the Eggenberg family became extinct in 1717, ownership of the town was returned to the Austrian Emperor who merged its territory with that of the County of Gorizia. In 1918 it was annexed to Italy.