The haunting ruins of this military fortress-turned astronomical observatory sit on a Sarajevo mountaintop. It was once the only facility of its kind in the area, and remains an important symbol of Sarajevo. The white building still looks over the city from Mount Trebević, though today the walls are crumbling and decrepit. Without Čolina Kapa, astronomy is virtually nonexistant in Bosnia and Herzegovina, despite the fact that the study of the stars reaches back to the 15th century in the region.