The Great Wall of China consists of a series of ancient walls and fortifications located in northern China, constructed over 500 years ago. Its length is estimated to range from 1,500 miles to 5,000 miles, but an archaeological survey by the Chinese National Heritage Administration in 2012 revealed that the actual length is more than double that, approximately 13,000 miles to 21,000 kilometers. How much do you really know about this iconic ancient structure?

1. You Can’t See It from the Moon
American cartoonist Robert Ripley made a fortune with his “Believe It or Not!” series, where he claimed that the Great Wall was “the only human-made structure visible from the Moon.” Of course, this statement was completely unfounded, as it was made 30 years before anyone had even gone to space. Yet, it was widely accepted. Even the famous sinologist Joseph Needham, author of Science and Civilisation in China, claimed that the Wall was “the only man-made feature visible to Martian astronomers.” Despite the widespread belief among astronauts, it wasn’t until 2003, during China’s first spaceflight, that astronaut Yang Liwei reported that he couldn’t see anything from orbit. The truth was firmly established at that point.
2. No Bodies Are Buried in the Wall
According to the ancient legend Meng Jiangnu Weeps at the Great Wall, workers were supposedly buried in the Wall. This myth likely originated from Sima Qian, the chief historian during the Han Dynasty, who criticized his predecessor to flatter his own emperor. However, no bones have ever been found in the Wall, and there is no written or archaeological evidence to support this claim, proving it to be mere slander.
3. The Wall Has More Than One Wall
The Great Wall is not just “a wall,” but “walls.” It’s not a single continuous structure but a series of walls. Some parts appear dilapidated, overgrown, and impassable, where wildlife has reclaimed the space. In many places, the walls are doubled, tripled, or even quadrupled in thickness, and these walls overlap in time. Some sections of the Wall near Beijing even have older foundations, with some portions directly beneath current structures. These segmented parts are much less significant when compared to other sections, which extend in parallel lines or scattered segments westward.
4. It Was Never Immune to Invasions
Before the Great Wall was built, northern tribes could easily cross or bypass the Wall’s locations. In 1449, the Mongols defeated the Ming forces south of the Great Wall, and it was not until the peaceful period between 1571 and 1644 that construction of the Wall was completed. However, in 1644, the Ming general Wu Sangui opened the gate at Shanhai Pass to the invading Manchu forces, allowing them to take control of the Wall.
5. It’s Not Wide Enough for Five Horses Side by Side
The commonly cited claim that the Wall’s width can accommodate five horses side by side only applies to certain sections of the Wall near Beijing. Other parts, especially those spanning the ridges of Simatai Mountain, are only wide enough for one person to pass. Further west, there are often no walkways, and soldiers or horses had to move along the base of the Wall.
6. Marco Polo Did See It
It is sometimes argued that Marco Polo never mentioned the Wall as evidence that he never visited China. However, the reality is that by the late 13th century, China was under Mongol rule, and the Wall had already become redundant since the Mongols had taken over northern China nearly 50 years earlier under Genghis Khan. During the time of war, the Mongols ignored the Wall, and there was no need to mention it in peaceful times. Marco Polo, traveling from Venice to the capital of Dadu (modern-day Beijing), would have crossed the Wall multiple times, yet there was no reason not to notice it.
7. It Was Not Built to Defend Against the Mongols
The Great Wall was commissioned by Emperor Qin Shi Huang, who died in 210 BCE, long before the Mongols appeared around 800 CE. At that time, the primary threats came from the Xiongnu, not the Mongols. The intense conflict between the central plains and the Mongols occurred much later, in the late 14th century, when the Mongols were eventually driven out of central China by the Ming Dynasty.