Knin Fortress is a partially preserved stronghold located just above Knin town in inland Dalmatia. It is one of the biggest and most significant defensive strongholds and a historical town in the Šibenik-Knin County. The construction of the fortress started as early as 9th century, while the current state was brought up in 17th and 18th centuries. It reached its peak during the reign of Demetrius Zvonimir, King of Croatia from 1076, as it served as a political centre of the Croatian Kingdom at the time.
It is situated on the main transport corridor leading from Dalmatia to continental Croatia and Bosnia. The Knin Fortress lies on top of the steep Spas Mountain, just 100 meters above the modern town. Archaeological excavations date that this area was populated since the 6th century. It is 470 metres long, and 110 meters wide, elevated at 345 metres above the sea.