Knin Fortress (Croatian: Kninska tvrđava) is a partially ruined fortress located just above Knin, Croatia. It is one of the biggest and most significant defensive strongholds, and a historical town in the Šibenik-Knin County in the Dalmatian hinterland. The construction of the fortress started as early as 9th century, while the current state was brought up in 17th and 18th centuries.[4][5] It reached its peak during the reign of Demetrius Zvonimir, King of Croatia from 1076, as it served as a political center of the Croatian Kingdom under him.[5]