The Alba Carolina Citadel is a star-shaped Vauban fortress covering over 70 hectares on a hilltop above the Mureș River. Built by the Habsburgs in the early 18th century, it is one of the largest and best-preserved examples of Baroque military architecture in southeastern Europe. The restoration completed in the early 2010s brought the gates, walls, and interior streets back to something close to their original appearance.
The fortress has six monumental baroque gates, each decorated with reliefs and statues. The most impressive is Gate III, flanked by allegorical sculptures representing war and peace. Inside the walls you'll find cobblestone streets, two major cathedrals side by side, a history museum, the university, and dozens of 18th-century buildings. The whole complex is pedestrianised and very walkable. A changing-of-the-guard ceremony takes place at the main gate daily in summer.