Viewed from above, the Qin Shi Huang Mausoleum looks like a four-side pyramid, so some people regard it as an earthen pyramid. However, according to researchers, it is composed of 9 layers of packed earth, making it even larger in size than the Great Pyramid of Giza in Egypt! What’s more, the underground section is a gigantic inverted pyramid of the same size as the one above ground. Some people claim that there are demons and ghosts haunting each underground layer. Others guess that Qin Shi Huang built these underground layers in order to let his soul freely wander. But why he built 9 layers above ground is still a mystery.

Emperor Qin Shi Huang (259BC-210BC) died in the Shaqiugong area during his inspection tour, where Xingtai City, Hebei Province is now located. It was in summer, so Qin Shi Huang’s body decomposed very quickly. At that time, it could take his attendants more than 50 days to carry the body back to the capital Xianyang in today’s Xi’an, Shaanxi Province. However, in the heat of summer, the stifling coffin could only accelerate decomposition. So, some people speculate that Qin Shi Huang’s attendants didn’t know how to preserve the body and had to bury him on the spot. What they took back to the mausoleum were simply the emperor’s clothes and belongings. However, as the mausoleum has not been excavated, it remains a mystery.
Read more: Where was Emperor Qin Shi Huang buried?

Through magnetic resonance imaging, archaeologists are sure that there are a lot of copper and silver coins in the Underground Palace of Qin Shi Huang Mausoleum. Thus, many people theorize that this place was built as a treasury or vault by Qin craftsmen. In fact, a similar description can also be found in the Chinese ancient book, the Historical Records written by Sima Qian of the Western Han (202BC-9AD). The book recorded that the Underground Palace was decorated with various pearls and jewels, whose brilliance could only be compared with the sun and the moon. Large chunks of gold and jade were piled to simulate rolling hills and mountains. If the record is true, the underground palace would be a real ‘treasury”.

As the most well-known component of the Qin Shi Huang Mausoleum, the Terracotta Army brings researchers not only vivid terracotta statues and bronzewares, but also human bones. The researchers collected the DNA data from these bones, and compared them with those of modern people. Surprisingly, one bone turned out to be from a Persian, and this meant that overseas laborers also participated in building the Terracotta Army more than 2,200 years ago. This discovery can be considered sound proof of Chinese interaction with other regions during ancient times. But why were people from other regions outside employed? Much more research is needed.

Some people worry that the Terracotta Army will deteriorate the future. Considering the oxidation and other pollutants in the air, the facial details of Terracotta Warriors may gradually disappear, and their arms and legs could also fall off. If that really happens, the Terracotta Army will have no aesthetic values at all. Luckily, Chinese and overseas archaeologists have already come up with some protective measures, and the erosion can certainly be prevented to some extent. However, whether the Terracotta Army will deteriorate or not in the future is still unknown. This is also one of the reasons why the Terracotta Army has not been fully excavated.

Record has it that Xiang Yu, the King of Western Chu (206BC-202BC), once sent 300,000 people to dig the Qin Shi Huang Mausoleum. During the excavation, a wild goose of gold suddenly flew out of the Underground Palace and flew to the south. Several hundred years later, during the Three Kingdoms (220AD-280AD), a prefecture chief called Zhang Shan received a golden wild goose and he was astonished to find that this wild goose used to be in the Qin Shi Huang Mausoleum. That’s to say, if the record is true, this wild goose kept flying in the Underground Palace for thousands of days, and then managed to reach a remote southern region. Obviously, it is nothing more than an interesting legend to stimulate people’s interest in the mausoleum.

The question about mercury in the Mausoleum of Emperor Qin Shi Huang constantly evokes people’s curiosity. Actually, researchers have determined that the mercury level of the mausoleum mound is truly higher than normal. Record also has it that there are rivers and lakes in the Underground Palace made from mercury. However, considering this mausoleum’s depth of 30m (98ft), the total volume of mercury is estimated to be several hundred tons, which was not easy to obtain at that time. And some people also questioned how the large amounts of poisonous mercury were put inside? These conflicts make the existence of large amounts of mercury a big question mark.

In order to protect the Underground Palace from water erosion, the Qin people built a large dam. Its lower part, with the thickness of 17m (19yd), was made of packed mud, and its upper part, with the thickness of 84m (92yd), was made of yellow soil. This design prevented underground water from rising upward. By using modern technology, researchers found that there is still no sign of water in the Underground Palace, while the area outside the dam contains underground water. This proves this marvelous drainage design still works to this day.

It is said that the Qin Shi Huang Mausoleum has three lines of defense to deter robbers. The first line in legend is sand. The edge of the whole mausoleum is filled with large amounts of sand. Therefore, thieves were not able to dig a hole and enter the inner mausoleum. The second line is made up of hidden crossbows, which does have historical record. Once robbers trigger certain devices in the mausoleum, the crossbows hidden in the gate and passageways will shoot from every direction. There is also an auxiliary design – a trap. Once intruders fall into the trap, they can never get out. The third line of defense is the mercury river mentioned already. In legend, it flows around the mausoleum giving out poisonous steam. Anyone who breathes this steam will die. However, like some of the above mysteries, they have not been proved true yet.