The wall is protected by a layer of biocrusts created by cyanobacteria, mosses, lichens and microbiomes. It could be called a “living skin”, and a study published in December last year clearly outlined how the crust played a crucial role in ensuring the long-term endurance of the wall.

Traditionally, scientists have viewed plant life as potentially destructive to ancient artefacts, with roots systems potentially tearing apart the structure of the wall. But that long-held belief is being challenged, and the recently published study analysed huge portions of the wall, discovering that bare parts of the structure were far less stable than those covered in biocrust.

Rather than causing erosion, the biological layer may be doing the exact opposite by protecting the wall from the elements.

Grenades popular along wall during Ming dynasty

One of China’s most famous inventions is gunpowder, so it makes sense that its armies would use the explosives to defend its most precious structure.

In October last year, archaeologists unearthed nearly 60 rudimentary grenades in a weapons storehouse along the wall, adding to the over 400 such weapons discovered over the years.

The grenades date back to the Ming dynasty (1368-1644) and were rudimentary in design. They featured a round rock with a hole drilled into the top that would be filled with gunpowder.

The grenades were often stored inside hollow bits of stone so they could be easily retrieved in the case of an attack.

The weapons were popularised by Ming dynasty military general Qi Jiguang, who was fond of grenades while also being in a position of holding immense sway over Chinese military strategy at the time.

Mutianyu, a well-preserved section of the Great Wall of China, surrounded by green trees during summer. Photo: Shutterstock

One family continues to run the entire distance

Basic math suggests it would take 18 months to walk across the Great Wall of China, and one family has made it part of their legacy to run the entire length.

Following their father’s footsteps, Jimmy and Tommy Lindesay covered the 3,262-kilometre (2,027-mile) journey in 131 days, a remarkable feat, especially considering the wall is famous for its steep inclines and declines.

The brothers also completed the journey at the height of the coronavirus pandemic, making the feat more complicated. But, they said their father’s journey was more challenging when he became the first foreigner to run the wall in 1987.

The Lindesays grew up in China but said the greatest challenge was handling the people who were untrustworthy of foreigners during the height of the Covid-19 pandemic.

Another “Great Wall of China” exists in Guangzhou

The Great Wall of China is the world’s longest wall, but it is not the only one in the country with a Guinness World Record.

In Guanghzou in southern China, the company 21st Century Business Herald unveiled on February 22 a 39.904-metre replica of the wall made entirely of balloons.

Their depiction built outside of the Canton Tower is now the official Guinness Book of World Records holder of the title “Largest balloon sculpture of a landmark.”

The wall took 100,000 balloons to build and features three watchtowers, two corridors, and the gold-coloured balloons harken back to medieval times.

The balloon wall was built by 20 people as part of a larger campaign to raise awareness about shingles.

Jinshanling Great Wall is located in Luanping county, Chengde in Hebei province 130 km northeast of Beijing. Photo: Shutterstock

Parts of wall are not much of a defense

Despite popular imagination, the Great Wall of China is not a single structure, and it features overlapping walls build across thousands of years as well as significant gaps between the structures.

One notable segment of the wall is called the “Mongolian Arc”, and what remains can hardly be called a wall, with the trench used to build the wall being a more formidable defense structure than the wall itself.

The wall stretches across a large chunk of Inner Mongolia autonomous region in northern China and crosses into Mongolia itself.

One possibility is that the Mongolian Arc was built in haste after the Jin Empire got word of the impending invasion by Ghengis Khan in 1211, although recent research points to the hypothesis that it was an observation structure designed to manage the movement of nomadic tribes in the region.

A crucial role in WWII history

Most depictions of the battles fought at the Great Wall of China harken back to pre-modern times, but the wall also played a crucial role in the Second Sino-Japanese War.

After the Japanese invaded Manchuria on September 18, 1931, they set their sights on further conquest of China, and the garrisons near Shanhaiguan (the “Shanhai Pass”) in north China became important targets.

Shanhaiguan is where the Great Wall meets the Pacific Ocean, and the wall represented a symbolic border between the northernmost region of Manchuria and the core of mainland China further south.

When Japan launched its attack on Shanhaiguan in January 1933, the Chinese side was defiant but outgunned. Imagine, instead of Ming-era rock grenades, the Kwantung army launching tanks, bombers and warships towards the wall.

After a day of brutal fighting, the Shanhaiguan fell into Japanese control, marking the first of a handful of WWII battles fought on the wall itself.

When Japan launched its attack on Shanhaiguan in January 1933, the Chinese side was defiant but outgunned. Here is the Mutianyu section of the wall near Beijing. Photo: Shutterstock

Lady Meng Jiang collapsed the wall with her tears

One of China’s four great folktales is the story of Lady Meng Jiang and Wan Xiliang, a man fleeing the Emperor’s conscription to build his Great Wall.

When Wan was discovered in Meng’s garden, he was weak from fatigue and hunger, and the couple fell in love while he was being nursed back to health.

Unfortunately for the lovebirds, a jealous villager informed authorities about Wan’s presence, and he was apprehended and sent north to work on building the wall shortly after their marriage.

When Meng did not hear back from her husband, she visited the wall to track him down, only to learn that he had died and had been buried inside the wall.

Overcome with grief, Meng wept for three days at the foot of the wall. Suddenly, a massive section of the wall stretching over 1,200 km collapsed, revealing the remains of her dearly departed and many others who died while building the wall.

In 2006, this tale was included in China’s first edition of the National Intangible Cultural Heritage list published by the State Council.