Knin Fortress (Croatian: Kninska tvrđava) is located near the tallest mountain in Croatia, Dinara, and near the source of the river Krka.

According to other similar fortifications from that time, it is assumed that it was surrounded by high walls, while the construction was accommodated to the terrain; it is environmentally secured by steep slopes on some places.

Baroque stone gates are set on the main entrance to the fortress, where the doors are made out of oakwood and strengthened with iron nails.

On the same location a memorial was elevated to fra Lujo Marun (1857–1939), a friar who was the first to instigate archaeological excavations in this area, and to discover many remains of the old Croatian culture.

[6] The fortress contained few ceremonial halls and the palace of the Croatian rulers, in which they issued their documents and lived with their courtiers during their stay in Knin.

It is possible that, in the 15th century, during the raising danger of the Ottoman advance towards Europe, an additional railing defensive wall was constructed on which the main entrance to the fortress is situated today.

The oldest known graphical presentation of Knin was recorded on a map of northern Dalmatia and Lika by a Venetian cartographer Matteo Pagano (1515–1588), in about 1525.

However, the more detailed description of the urban appearance of the fortification was handed by another Venetian, the military engineer named Orazio Antonio Alberghetti (1656–1690) in one of his schemes made at the time of the expulsion of the Ottomans in 1688.

Following the capture of Knin (capital of the self-proclaimed proto-state Republic of Serbian Krajina) on 5 August 1995, the flag was firstly raised by the commander of the 7th Guards Brigade ("Pumas") of the Croatian Army, General Ivan Korade, and the next day by the President of Croatia Franjo Tuđman as well.