Serbia does a fine line in grisly historical monuments, but few invoke as much terror and disgust as the is-exactly-what-it-says-it-is Skull Tower. Located in Niš, the name doesn’t really leave any question marks over the primary material used to construct the tower. In short, this tower was once made out of skulls, human skulls.

The Ottoman occupation of Serbia was brutal, to say the least. The Serbian population and culture was stuck under the gigantic boot of the Islamic empire, and the Ottomans weren’t shy when it came to stamping down. Rebellions were as inevitable as they were frequent, but by the 19th century these attempted revolutions came with added vigour and renewed enthusiasm. The First Serbian Uprising kicked off in 1804, although poor organisation eventually worked against the Serbs. The situation looked dire once again.

Serbian leaders found themselves fighting losing battles, vastly outgunned and outnumbered. This was the case at the Battle of Čegar in May 1809, but the Serb leader (a man by the name of Stevan Sinđelić) was about to go down with all guns blazing — he was going to take as many Ottomans out as he could. His trench was overran and he subsequently blew the whole thing up, ending the life of anyone and everyone in the vicinity, no matter which uniform they had on.

Angered by this suicidal move, Ottoman Grand Vizier Hurshid Pasha demanded the skulls of the rebels be sent to Sultan Mahmud in Constantinople, who decided that the best course of action would be to build a monument that might put the fear of death into the Serbs in and around Niš. 952 skulls were built into a tower, 14 ghastly rows of 17 skulls on four sides. Thus the Skull Tower in Niš came into being.

It turned out that skulls aren’t the best material with which to build a tower, and the dismembered heads subsequently started to fall out. Plenty of the skulls were stolen as well, as the Serbs looked for new ways to irritate their Ottoman overlords. The empire was running out of steam, and the tower eventually became a symbol of defiance for the Serbs as opposed to a warning. On January 11, 1878, Niš was once again under Serbian control.

The Skull Tower is now a protected monument of the city, one of its most famous attractions and a tangible piece of evidence showing the horror under which the Serbs lived for centuries. Less than 100 skulls remain in the tower today with that number dwindling all the time, although the Skull Tower will forever live on in the Serbian consciousness.