Duino Castle is a fourteenth-century fortification located in Duino, near Trieste, Italy, on the cliffs overlooking the Gulf of Trieste. Building commenced in 1389 at the order of the Wallsee family. The ruins of an older castle built in the eleventh century by the Patriarch of Aquileia are located on the grounds.

Trieste is the capital city of the Friuli Venezia Giulia region in northeast Italy. A port city, it occupies a thin strip of land between the Adriatic coast and Slovenia’s border on the limestone-dominated Karst Plateau. Italian, Austro-Hungarian and Slovenian influences are all evident in its layout, which encompasses a medieval old city and a neoclassical Austrian quarter.