The White Fortress is an old fort overlooking the historic core of Sarajevo. It is a national monument of Bosnia and Herzegovina. Bijela Tabija is 667 metres above sea level.
Bijela Tabija is a protruding part of the wall of what was historically known as the old Vratnik City, and dominates the Eastern, the natural entrance to Sarajevo. It is built of stone and it used to house a gun-crew and an ammunition storage. Its thick walls have openings for cannons.
Wikipedia https://en.wikipedia.org/wiki/Bijela_Tabija
Coordinates 43°51'33.832" N 18°26'40.287" E