Blagaj Fortress

Blagaj Fortress or Old Town of Blagaj, locally known as Stjepan-grad, or Stipan-grad, in classical times Bona, is a town-fortress complex near the town of Blagaj, Bosnia and Herzegovina. The old Blagaj Fort was built on a high, inaccessible karst hill, at an elevation of 310 metres above sea level and 266 metres above the source of the river Buna. Blagaj Fort is 275 metres above sea level. Fortress is National monument of Bosnia and Herzegovina, declared by KONS on 6 December 2003.

Source: Wikipedia