Blagaj Fortress, locally known as Stjepan-grad is a town-fortress complex near the town of Blagaj. The old Blagaj Fort was built on a high, inaccessible karst hill.
The archaeological material scattered above the slopes of Blagaj hill indicate that settlements existed here during the prehistoric and Roman periods, however it’s named after a 15th century count (herceg) Stjepan Kosača. After the 10th century, Blagaj played an important role in the development of Hum or Zahumlje. A major influence on its development was the proximity of a major route linking the Adriatic sea with the Bosnian hinterland via the Neretva valley (“via Narenti”).
The first written reference to it is a peace accord between Duke Sandalj Hranić and the Venetians, from November 1, 1423, issued “in our town of Blagaj”. It was also mentioned in the 15th century charters of the King of Aragon and Naples, Alphonse V.
The Ottomans occupied Blagaj in 1465, and by 1473 references to the kadija of Blagaj already exist. The Ottomans repaired the fort twice: in 1699, when the west tower was repaired, and again in 1827. A garrison was stationed there until 1835, although the fort’s former strategic role had long since been taken over by Mostar.
The Fortress Stjepan grad was placed under state protection. The historic site of the Old Fort in Blagaj (Stjepan grad) is also on the Provisional List of National Monuments.