The Great Wall of China was built 2,000 years ago during the 14th through the 17th centuries. It stretched over 5,000km and later expanded to 6,400km. In most places the wall was 4.5 to 9 meters (15 To 30ft.) tall. It is the largest structure ever built.
The Great Wall of China has a very long and interesting history. During the dynastic period, five major walls have been built.

1. 208bc (the Qin Dynasty)
2. 1st century BC (the Han dynasties)
3. 1138-1198 the 5 dynasties and 10 kingdom’s period
4. 1368-1620 (From Hongwu Emperor until Wanli Emperor
5. The Ming Dynasty wall (it stretched over nine provinces and 100 counties).

The government ordered people to work on the wall. Workers on the wall were under perpetual danger of being attacked by brigands. Because many people died building the wall, it earned a nickname - “The long graveyard. Despite the common rumor, no workers were buried in the wall because it would weaken the structure. Instead the bodies were buried nearby. Most of the historic wall is not well preserved, and today, it is very prone to vandalism. The primary purpose of the wall was not to keep out people who could scale it, but to insure that semi-nomadic people on the outside of the wall could not cross with their horses or return easily with stolen property. It protected China from Mongols and from Turkic tribes.
The Great Wall can be seen from orbit, although an officer aboard ISS (International Space Station) stated the wall is harder to see than some other things. One of the reasons it’s harder to see The Great Wall than other things is because it’s only a few meters wide. Another reason is that it’s also the same color as the soil around it, and it looks similar to runways and highways. A photo from ISS confirms that the Great Wall can be seen with the naked eye; you just need to know where to look.

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