Novi Sad is a city in northern Serbia on the banks of the Danube River. Standing atop a riverside bluff, much of Petrovaradin Fortress dates to the 17th and 18th centuries, with an iconic clock tower and a network of tunnels. Across the river is the old quarter, Stari Grad, site of the Gothic Revival Name of Mary Church and the neo-Renaissance City Hall.
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Serbia is a country on southeast Europe's Balkan peninsula with northern plateaus and mountains with ski resorts to the south. Capital city Belgrade is home to Communist-era architecture and Kalemegdan Park, site of Belgrade Fortress, held successively by the Roman, Byzantine and Ottoman empires. Stari Grad, the old city, is home to 19th-century mansions, plus opera and ballet at Narodno Pozori?te (national theater).

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