The Great Wall
By Jenny McGlone
Chapel Hill, NC, United States
Most students of history have heard of China’s Great Wall. Scholars seem to agree that this wall was constructed many centuries ago on an east-west orientation to protect China from neighboring invaders to its north. Much of the wall fell into ruin as the need for such protection subsided. In fact, one historian figured out that only 8.2 percent of it remains intact, while another 22 percent of it has completely vanished.
How Long Was It?
Did you know that nobody is sure how long the Great Wall really was? Until a few years ago, estimates centered on 5,500 miles. Recently, however, archaeologists have proposed that the actual original length was closer to 13,170 miles. Not all of this was built by humans, as rivers, steep mountains, and other natural barriers were incorporated into the Wall. Stretched out, this Wall could run more than halfway around the globe!
How and When Was It Built?
The first sections of the Wall were constructed as long ago as the eighth century BCE, using mud and gravel that was packed together. With the invention of brick-making during the Tang Dynasty (618-907 CE), these sturdier, lighter components were preferred. One of the ingredients in holding the bricks to each other was sticky rice juice!
You may be interested to know that the Wall was not just a wall. The builders thought of every possible defensive need, so they included other structures:
- drainage systems
- ramps for horses
- barracks for soldiers
In the best-preserved, Mutianyu section of the wall, reinforced with granite in 1569, there are 23 watchtowers along 2,250 meters.
How Tall Was It?
The Mutianyu section’s average height is seven to eight meters in height, four to five meters in width. The top of the Wall is narrower than the bottom. In some places, now, the Wall has eroded to fewer than two meters.
Can It Be Seen From Space?
Despite the Wall’s size and length, the popularly held belief that it can be seen from the moon is actually false. Scientists have estimated that it would need to be 70 miles wide to be viewed with the unaided eye from such a distance. Another comparison would be trying to see a human hair from two miles away. NASA has published photographs disproving this myth, so you can see (or rather, not see) for yourself.
Have a suggestion for this story? We’d love for you to submit it!
- How many times back and forth across the US could the Great Wall go?
- If only 8.2 percent of the wall remains intact, how long is that?
- If 22 percent of the Wall has vanished, how much length is that?
- It took 500,000 people to build the Wall. Look up the population of China during the Ming Dynasty and figure out what percentage of the population that was.
Social Justice Question
Many workers were seriously injured or killed during construction of the Wall. Since it was built for protection, was this loss of life justifiable? Why or why not?
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