St Nicholas’ Fortress - part of a six Venetian defence fortifications

St Nicholas' Fortress was built in the mid-16th century to protect the city of Šibenik and its port, including the Krka delta and the city of Skradin against sea-based attacks.
The fortress is part of a line comprising six Venetian defence fortifications, which extends as far as 1000 kilometres, from the Italian region of Lombardy, along the Adriatic coast of Croatia, all the way to Montenegro. The fortifications throughout the Stato da Terra protected the Venetian Republic and its landlocked hinterland, while those of the Stato da Mar protected the sea routes and ports in the Adriatic Sea to the Levant.