St. Nicholas Fortress.

St. Nicholas Fortress, built in the 16th century at the entrance of St. Anthony's Channel near Šibenik, Croatia, is a remarkable example of Venetian military architecture, entirely surrounded by the sea. Designed by architect Giangirolamo Sanmicheli to protect the city from Ottoman naval attacks, this fortress showcases unique Renaissance features and has never experienced a major siege, instead serving as a deterrent against invaders. Recognized as a UNESCO World Heritage Site in 2017, it sits within a protected area rich in biodiversity. Following restoration completed in 2019, visitors can explore its historic walls via organized boat tours or land access. The fortress offers an engaging glimpse into the past, merging cultural heritage with stunning natural surroundings.