Automatic Crossbows And Rolling Boulders: Are Booby-Trapped Tombs Fact Or Fiction?


Jack Dunhill


Jack Dunhill

Social Media Coordinator and Staff Writer

Jack is a Social Media Coordinator and Staff Writer for IFLScience, with a degree in Medical Genetics specializing in Immunology.

Social Media Coordinator and Staff Writer


A tunnel within Chauvin de Huantar's temple. Image Credit: Christian Vinces /

A giant boulder hurtling down an inescapable passage; a wall of crossbows that fire the moment a golden item is touched; a pit of spikes beneath a carefully-laid straw floor. These are just some of the booby traps that have become synonymous with the tombs of ancient rulers, whether it be Indiana Jones or Lara Croft exploring their depths. 

But despite their fame and the everlasting love for booby-trapped adventures, is there any truth to it? Could it be possible that the tomb of an ancient Pharoah still contains a fully functional booby-trap system? 


Before we get into it, let's dispel a quick point – no, there is no evidence of a rolling boulder trap found in any real tomb. Sorry to crush your dreams, but that was entirely fabricated by some very imaginative storytellers. This is also true for the more outlandish traps, such as poison darts and crazy counter-weight systems. There are, however, some pretty cool discoveries deep in ancient tombs that were likely could have deterred thieves. 


The Mausoleum of the First Qin Emperor: Rivers of Mercury and Automatic Crossbows 

The Mausoleum of the First Qin Emperor, containing the body of Qin Shi Huang, is one of the most notorious tombs in the world. Famous for containing a number of hazards that have prevented its full exploration, it is also one of the most impressive underground burial places in the world, featuring an entire chamber of terracotta warriors. Constructed over 2,000 years ago, somewhere between 246 to 208 BCE, the mausoleum lies beneath a gigantic mound to house the "army" that protects the inner tomb. At its center lays the remains of the first emperor of the Qin Dynasty, a legendary leader that ruled the first unified China. 

Meet the terracotta warriors that guard Shi Huang. Image Credit: DnDavis /

As you might’ve guessed from the army of fake warriors, Qin Shi Huang wished to be protected greatly even after he passed. The tomb itself has never been excavated, mainly due to the abnormally high levels of mercury in the mausoleum. See, Qin Shi Huang (like many others at the time) believed mercury could bestow immortality, and as such allegedly created a moat of the toxic metal to surround his tomb. Stories tell of a large system of rivers and lakes containing the shiny substance, and have certainly worked in preventing entry. This is disputed, however, and others suggest the mercury is simply a result of industrial pollution in the area. Either way, the toxic system of mercury and groundwater makes the tomb a tough area to breach. 


Impressively, a possible river of mercury is not the coolest contraption Qin Shi Huang used to defend his remains. Legends state that the tomb itself contains a trap system of automatic crossbows, ready to pump intruders full of arrows the moment they attempt to desecrate his remains.  

The biography of Qin Shi Huang, written by Sima Qian, says as follows: 

“Palaces and scenic towers for a hundred officials were constructed, and the tomb was filled with rare artifacts and wonderful treasure. Craftsmen were ordered to make crossbows and arrows primed to shoot at anyone who enters the tomb. Mercury was used to simulate the hundred rivers, the Yangtze, Yellow River, and the great sea, and set to flow mechanically.” 

While the crossbows, if they exist, will probably not be functional after 2,000 years, it does suggest elaborate contraptions were considered as tomb protection.



Egyptian Tombs 

Rivers of mercury and automatic crossbows are a tough act to follow, and Egyptian tombs didn’t quite live up to their Chinese counterparts. Of course, these tombs date from much further back than the Mausoleum of the First Qin Emperor, this time dating to well over 4,000 years old, but that didn’t stop them from getting crafty when protecting against tomb raiders. 

Instead, construction workers of important tombs turned to decoys and fake walls to deter robberies. Hidden within the Great Pyramid of Giza, an elaborate tunnel system takes archaeologists to the tomb of what is believed to be Pharoah Khufu, who ruled around 2500 BCE – or so they think. Khufu’s mummy was never found, with the King’s Chamber already robbed prior to its’ discovery many years later. But some archaeologists believe this chamber was a decoy, and a secret chamber instead houses the king. This has never been verified, but a number of empty chambers and dead-end passages could point to a hidden tomb. 


The Red Queen of Palenque 

To finish off our small tour through ancient booby-trapping, we have a Queen who would stop at nothing to prevent others from touching her bones. Buried in a Mayan pyramid in the ruins of the city of Palenque lies the Tomb of the Red Queen, an ancient tomb dating back around 1,400 years. 

The remains are likely of Lady Ix Tz'akbu Ajaw, but all that has been confirmed is that the Lady was of great importance at the time. Surrounded by wealth and riches, the tomb was lavishly decorated and the remains were wearing an ornate funerary mask inside a sarcophagus. However, lifting the sarcophagus left the archaeologists with quite a shock – the bones were covered in a vibrant toxic substance.

Bright red cinnabar, the ore of mercury (ancient rulers really like mercury), coated the bones and contaminated the surrounding jewels, giving her the nickname the Red Queen. Handling the bones required intense care, as cinnabar is extremely toxic, despite its use as an early red pigment. It is likely the Red Queen wished for her decoration purely as a visual spectacle, and not as a deadly deterrent, but the end result is one that made stealing her jewels a seriously bad idea for grave robbers.

The Tomb of the Red Queen looks exactly like a Hollywood tomb should. Image Credit: Ocean Eloy/
So, there you have it – while death-defying traps may not have stood the test of time, it does appear many tombs were still dangerous places to sneak into, sometimes unintentionally. If you happen to find yourself in an ancient tomb, maybe watch your head.


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