The Black Sea town of Sozopol in Bulgaria has become home to the buried remains of “vampire skeletons.”

These skeletons date back to the Middle Ages. It is reported that Bulgaria is home to at least 100 skeleton burials of vampires.

In Slavic folklore, the existence of vampires was a tradition that was common but it was especially popular in Bulgaria. The vampire was considered to be a beautiful supernatural being who sucked the blood from maidens. The only way to kill the vampire was to plunge a wooden stake or rod into his chest.

In 2014, archaeologists discovered many graves that contained skeletons with wooden or iron rods pierced through their chest cavities. Some of the graves were older than the Middle Ages. However, Bulgarian historians claimed that the practice of pinning the dead with rods was common in some villages until the first decade of the 20th century.

The belief that the villagers had was that the dead would be prevented from rising up at midnight and terrorizing everyone. For the villagers, plunging an iron rod was not the only way to kill a vampire. They also had the skeleton’s teeth pulled.

Evidence of the pulled teeth was found in a toothless 700-year-old skeleton found in church ruins in Sozopol. The skeleton had also been stabbed with an iron rod.

The skeletons and the superstition about the vampires in the area eventually led Bram Stoker to write about his famous fictional character, Dracula, in 1897.

As for the vampire skeletons of Bulgaria, historians still consider the origin of the superstition to be a mystery.