Fortress
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Petrovaradin Fortress
Nicknamed the 'Gibraltar on the Danube', Petrovaradin Fortress in Novi Sad is one of Europe's largest and best-preserved military fortifications. Built by the Habsburg Empire between 1692 and 1780 to defend against Ottoman expansion, the fortress features a staggering 16-kilometer multi-level underground countermine tunnel system (Lagumi). Countless soldiers, prisoners, and masonry workers perished during its century of construction and violent sieges. Today, its dark catacombs, reverse-handed clock tower, and secret subterranean passages generate endless stories of phantom soldiers, shadow figures, and subterranean hauntings.