Nikole) is a fortress located at the entrance to St. Anthony Channel, near the town of Šibenik in central Dalmatia, Croatia.

St. Nicholas Fortress was built on the left side at the entrance to St. Anthony Channel, on the island called Ljuljevac.

At the request of domestic Croat population of Šibenik, the Venetian captain Alvise Canal decided to build a fort on the island of Ljuljevac on 30 April 1525.

Although defense capabilities of the fortress have never been tested in military operations, the structure still proved successful in protecting the city from sea-bound enemy attacks.

During the centuries of use, the structure served to various armies and has undergone a number of renovations, some of them necessary only because of the development of arms.