Knin Fortress (Croatian: Kninska tvrđava, Tvrđava Knin) is a one of the biggest and one of the most significant fortresses located above Knin, a historical town in the Šibenik-Knin county in the Dalmatian hinterland, Croatia.
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 above the Croatian historical town of Knin, which was formed quite early at the foothills of the same mountain.
Croats built the fortress near a devastated Roman settlement, soon after they settled in the area. The fortress and the town experienced their highest glory during of one of the most important Croatian kings Dmitar Zvonimir, when Knin was Croatian capital and the seat of the Croatia’s bishop.