Doboj Fortress Gradina

Dobojska tvrđava je poznati srednjovjekovni grad na području Doboja, Bosna i Hercegovina. Doboj Fortress is a famous medieval town in the area of Doboj, Bosnia and Herzegovina. It was built on a conical rocky hill above the valley of the river Bosna, opposite the mouth of the river Spreča. Slightly further south is the mouth of the Usora River in Bosnia.