|Petrovaradin fortress (Serbian: Петроварадинска тврђава or Petrovaradinska tvrđava) is a fortress on the Danube river, near Novi Sad in the Serbian province of Vojvodina. The cornerstone of the present-day southern part of the fortress was laid on October 18th, 1692, by Prince Croy. The Petrovaradin fortress has many underground passages as well (16 Km of underground countermine system).|
The area of Petrovaradin, today within the Novi Sad city area, was inhabited by the Celts, in the 1st century BC. In the area between Sremska Kamenica and Petrovaradin, a fortress was raised by the Romans, who replaced the Celts two centuries after. The fortress was known as "Cusum". Although there was no fortress on the foundation of the present-day Petrovaradin fortress, the rock was used as an observation post. Three centuries later, the Huns desecrated the area. The Western Roman Empire then fell, and the Byzantine empire soon established their borders around Petrovaradin. Cusum's name was changed to Petrikon.
Belgrade fell in 1521, making the real danger now the Ottoman Empire. Wanting to reach Vienna and Hungary, the Ottoman empire moved north-west, taking Petrovaradin. Petrovaradin was conquered on July 27th, 1526. For 161 years, under Turkish rule, the fortified area of Petrovaradin received no attacks. When the year of 1687 arrived, the Austrian army took over the fortified area, and started building up new defensive posts. The Austrian army had another victory, on August 17, 1691. This is when the construction of the present Petrovaradin fortress took place a year after. Many Turkish objects, and objects from the Medieval era were demolished, making the fortress have the appearance that it has today. Prince Savoy, Count Carafa, Field Marshal Kaprara and the heir to the throne Joseph II oversaw the construction of the newer fortress.