The Belgrade Fortress, consists of the old citadel and Kalemegdan Park on the confluence of the Sava and Danube rivers, in an urban area of modern Belgrade, Serbia. Located in Belgrade's municipality of Stari Grad, the fortress constitutes the specific historical core of the city. As one of the most important representatives of Belgrade's cultural heritage, it was originally protected right after World War II, among the first officially declared cultural monuments in Serbia. The fortress was declared a Monument of Culture of Exceptional Importance in 1979, and is protected by the Republic of Serbia. It is the most visited tourist attraction in Belgrade, with Skadarlija being the second. Since the admission is free, it is estimated that the total number of visitors is over 2 million yearly.

The Kalemegdan Park, or simply Kalemegdan is the largest park and the most important historical monument in Belgrade. It is located on a 125-metre-high (410 ft) cliff, at the junction of the River Sava and the Danube.