AP

A piece of iron lies next to a skeleton dating back to the Middle Ages at an archaeological dig in the Black Sea town of Sozopol. Bulgarian archaeologists say they have found skeletons that were pinned down through their chests with iron rods - a practice believed to stop the dead from rising as vampires.

Bulgarian archaeologists are showing off two centuries-old skeletons that they say were pinned down through their chests with iron rods to keep them from turning into vampires — a trend that was all the rage in medieval Europe.

The "vampire" skeletons were excavated recently near the Black Sea town of Sozopol, according to reports from The Associated Press and AFP. Bozhidar Dimitrov, head of Bulgaria's National History Museum, was quoted as saying that corpses were regularly treated this way in some parts of the country until the beginning of the 20th century.

About 100 similar burials have been found in Bulgaria over the years. "I do not know why an ordinary discovery like that became so popular," AP quoted Dimitrov as saying on Tuesday. "Perhaps because of the mysteriousness of the word 'vampire.'"

Bulgarian archaeologist Petar Balabanov has found a number of nailed-down skeletons near the eastern town of Debelt, at gravesites dating as far back as the 1st century. According to custom, the bodies had to be pinned down just in case they tried to rise from the grave. AFP quoted Balabanov as saying that the rite was practiced in Bulgaria as well as other Balkan countries.

Of course, the world's most famous vampire legend is associated with the 15th-century Balkan strongman known as Dracula, or Vlad the Impaler. That's mainly due to Irish novelist Bram Stoker, who borrowed the Dracula name for his 1897 novel about a blood-sucking bad guy from Transylvania. The idea that vampires drank blood may be of relatively recent vintage, but the idea that the dead had to be stopped from rising again was widespread in medieval times — in part due to the plague.

Several years ago, Italian archaeologists made a splash when they dug into a mass grave for 16th-century plague victims on the Venetian island of Nuovo Lazzaretto and found the remains of a woman who had a brick stuck between her jaws. To explain the brick, they cited some of the anti-vampire strategies practiced at the time.

For example, in one region of Germany, gravediggers would occasionally return to a plague grave and find that the shroud surrounding the corpse had been eaten away, with blood or other fluids coming out of the mouth. The hair and fingernails also appeared to grow longer, even after burial. Today, researchers say such phenomena are due to the natural stages of decomposition — but in the Middle Ages, people feared that these were the signs of vampirism.

The Italian researchers claimed that the brick was jammed in to keep the "Vampire of Venice" from causing trouble. But other archaeologists have disputed that claim. They suggest instead that the brick merely fell into the mouth of the woman's skull. That has sparked a scientific tiff, as LiveScience reported last month.

Based on Balabanov's excavations, the Bulgarian nailing-down practice goes much farther back than Dracula or the Black Death — maybe like placing coins on the eyes of the deceased, but grislier. What do you think? Is this solid science, or another case of vampire grandstanding? Please feel free to weigh in with your comments below.

More about ghoulish archaeology:

• 'Vampire' victim spurs gruesome debate
• Black magic revealed in ancient tablets
• The science of bloodsuckers
• Gallery: Seven ghoulish discoveries
• Gallery: Myths and realities about vampires

Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.