Great Wall of China
The Great Wall of China is the longest wall ever built. If you joined together every section of wall ever built, it would stretch for over 21,000 km, about halfway around the Earth. It was built over many centuries to protect the heart of China from invaders from the north. The wall snakes through mountains, deserts and grasslands, with watchtowers along its length.
- CountryChinaAcross northern China
- Total lengthOver 21,000 kmAll sections combined
- First builtapprox. 700 BCEarly walls in the Spring and Autumn period
- Best-known sectionMing Wallapprox. 8,800 km, built 1368 to 1644
- BuildersMillions of workersSoldiers, peasants and prisoners
- Visible from space?NoDespite the popular myth
How long is the Great Wall compared to other long things?
All sections of the Great Wall combined are more than twice the length of the Trans-Siberian Railway, which is itself the longest railway on Earth.
What is the Great Wall of China?
The Great Wall is not a single wall but a collection of many walls, built and rebuilt over more than 2,000 years by different Chinese dynasties. Different sections are made of different materials: some of stone, some of earth packed between wooden frames, some of bricks. The wall winds through mountains, climbs steep ridges, and crosses deserts. Many sections include watchtowers, beacon towers (for sending signals by smoke or fire), gates and fortresses.
Who built it and why?
The first parts were built around 700 BC by small Chinese kingdoms. The first emperor of unified China, Qin Shi Huang, joined them up and extended them around 220 BC to keep out invading nomads from the north (especially the Xiongnu). Later dynasties continued to add and rebuild. The most famous and best-preserved sections were built by the Ming Dynasty between 1368 and 1644.
Building the wall was incredibly costly in lives. Soldiers, peasants and prisoners were forced to work in harsh mountain and desert conditions. Estimates suggest that around a million people may have died over the centuries of construction. Many were buried in the wall itself, which is sometimes called "the longest cemetery on Earth".
Did the wall work?
Sometimes. The wall was effective at slowing down small raids and giving the Chinese army time to gather troops. But against major invasions it often failed. The Mongols under Genghis Khan got past it in the 1200s by attacking gates that were left undefended. The Manchus invaded in 1644 by being let through by a defending general who switched sides. So the wall was useful but not unbeatable.
The wall today
About 30% of the Great Wall has now disappeared, eroded by wind and rain or torn down for building stone. The Ming sections nearest to Beijing are the best preserved and most visited, especially at Badaling (the most popular tourist section) and Mutianyu. Other sections, especially in the western deserts, are in much worse condition and very few people visit them. The Chinese government has spent huge sums on restoration since the wall became a UNESCO World Heritage Site in 1987.
Deeper dive: dynasty by dynasty, frontier strategy and ongoing decay
The Great Wall is really a layered record of two millennia of Chinese frontier policy. The earliest walls, built by states such as Qin, Zhao and Yan in the Warring States Period (approx. 475 to 221 BC), were short defensive barriers between rival Chinese kingdoms. The first emperor Qin Shi Huang (221 to 210 BC) linked these together and extended them as a single northern frontier after unifying China. The Han Dynasty (206 BC to 220 AD) pushed the wall further west into the Gobi Desert to protect the Silk Road. Later dynasties (the Northern Wei, Northern Qi, Sui, Liao, Jin and others) each rebuilt or extended sections.
The Ming Dynasty (1368 to 1644) carried out the largest and best-documented programme. The Ming had been founded after expelling the Mongol Yuan Dynasty, and lived in fear of further Mongol attack. They rebuilt much of the existing wall and added thousands of kilometres of new construction, mostly in brick rather than the earth and stone of earlier walls. The Ming Wall is the wall most people picture today: stone and brick, several metres thick, with watchtowers every few hundred metres, climbing steeply across mountain ridges.
Modern conservation of the Great Wall is difficult. Roughly 30% of the Ming-era sections have completely disappeared, mostly because the bricks were carted away by local villagers over the centuries to build houses and roads. Climate change is accelerating erosion in the desert sections. Mass tourism damages the most popular areas. Restoration is also controversial: some restored sections have been criticised for being too aggressive, essentially rebuilding the wall as a smooth modern surface that no longer resembles the original. The most pristine sections are the so-called "wild walls" in remote areas that have been left alone, slowly returning to nature.
The country is China. Another famous Asian landmark is Machu Picchu in Peru.