Kalemegdan is the largest Belgrade park and also the greatest cultural and historic complex, with the Belgrade Fortress in its centre. Before it was turned into a park in the late 19th century, the flat area around the fortress served as a military watch point. The Turks called it fićir-bajir (fichir–bayir), ‘a contemplation hill’. The fortress itself was built in the 1st century as a palisade (a fence of pointed pales) with earthen bulwarks as a defence against the barbaric tribes, and during the 2nd century it grew into a Roman military fort, castrum. After that it was a Byzantine castel (a defence fortress) and in the 6th century the Slavs settled around it. In the 14th and 15th century, the fortress was the heart of the Serbian capital, but after that period it was in turns a Turkish and an Austrian artillery fortification. Each of the invaders left its mark on the Kalemegdan Fortress walls. Its remains from the Roman times are now buried underground, just to emerge from time to time when the city has to do some digging – for instance, when the tram tracks have to be shifted. The remains of the Despot’s castle with the donjon tower (the area of the panorama plateau) is the very heart of Kalemegdan. The Lower Town walls and the Nebojša Tower also date from the Despot’s period. The Upper Town stone ramparts are mostly from the Turkish period, while the brick walls were built by the Austrians in the 18th century. The Kalemegdan Fortress is under constant renovations and extensions, while it is being invaded only by troops of tourists.
The word Kalemegdan is a compound word, consisting of two Turkish ones – kale, a fortress, and megdan or mejdan, an Arabic word meaning a vast field, an open city area, a square, a fairground, a marketplace, a place where duels are fought. Above all, Kalemegdan means an empty area before a fortress, the present park.
For the Turks, it was ‘The Gates of War’, and when it was in the hands of the Austrian rulers, as the last Christian fortress standing against the Turks, fortified Belgrade was also called “The Ramparts of Christianity”.
The Belgrade Fortress also used to have its outer ramparts which went through the present downtown area. The town could be accessed through several gates: the Istanbul Gates (Stambol-kapija), the Sava Gates (Savska kapija), the City Gates (Varoš kapija).