How Long Is the Great Wall of China Really?

How long is the Great Wall of China? Most people guess a few thousand kilometers. The official answer: 21,196 kilometers (13,171 miles). That is more than the distance from the North Pole to the South Pole. Chinese researchers spent five years measuring every section before publishing that number in 2012. And yet much of what you think you know about the wall is wrong. It is not one single wall. A big part of it has already disappeared. And no, you can't see it from space. Here is what's really behind the most famous wall in the world.

The official answer: 21,196 kilometers

The Great Wall of China is officially 21,196.18 kilometers (13,171 miles) long. The number comes from a survey by China's National Cultural Heritage Administration, published in 2012. Researchers spent five years mapping every wall section, trench, and fortress from all dynasties using GPS. It was the first scientific measurement of the entire wall ever done.

Before that, estimates were all over the place: anywhere from 5,000 to 50,000 kilometers. No surprise, because the wall was built over more than 2,000 years, by different rulers, in different regions. In the end, the survey counted 43,721 individual structures and remains: walls, trenches, watchtowers, and forts.

Longer than pole to pole: putting the number in perspective

21,196 kilometers is hard to picture. For context: Earth's circumference is about 40,000 kilometers. The wall would reach more than halfway around the planet. The distance from the North Pole to the South Pole is about 20,000 kilometers. The wall is longer.

One more comparison: New York to Los Angeles is about 3,940 kilometers (2,450 miles). You would have to drive that route more than five times to match the wall. And if you hiked 25 kilometers every day, you would be walking for roughly 850 days. That is about two and a half years, without a single rest day.

Why the Great Wall is not one single wall

The Great Wall is not one continuous structure. It is a network of many walls built over centuries. The oldest sections date back to around the 7th century BC. Later, China's first emperor Qin Shi Huang had many of these pieces connected. But what you know from photos are mostly the sections built by the Ming dynasty. They went up between the 14th and 17th centuries and stretch about 8,850 kilometers (5,500 miles).

And even the Ming wall is not all wall. About 6,259 kilometers are actual built wall. The rest is trenches and natural barriers like mountains and rivers that the surveyors simply counted in. Nature did a lot of the heavy lifting.

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Can you see the Great Wall from space?

No. The myth has been around for almost 100 years, but it is wrong. As early as 1932, a Ripley's Believe It or Not cartoon claimed the wall was the only man-made structure visible from the Moon. The problem: it isn't true. China's first astronaut Yang Liwei orbited Earth 14 times in 2003. Afterwards he said the Earth looked beautiful, but he could not spot the wall.

The reason is simple. The wall is extremely long, but only a few meters wide. And it is made of stone and rammed earth that barely stand out from the surrounding terrain. NASA confirms it: even from low Earth orbit, the wall is hard or impossible to spot with the naked eye. And from the Moon, nobody has ever seen it.

How much of the wall is still standing?

Less than you think. Depending on the count, roughly 22 to 30 percent of the Ming wall has already vanished completely, about 2,000 kilometers. Wind, rain, and sandstorms eat away at the rammed-earth sections. Then there are people: for decades, villages took stones from the wall as building material for houses and stables. Estimates suggest only a small part of the Ming wall is still in good condition.

By the way, the wall is not the only structure with record-breaking dimensions. In our article on the tallest structures in human history you'll find more buildings that defy imagination.

Remember one number: 21,196 kilometers, longer than pole to pole. If numbers like that hook you, you're in the right place. Try our geography estimation questions or test your knowledge with our history quiz questions. Free, no sign-up needed.