Did you know the reason why only in China you can find the Great Wall?
Looking at the map of the world, one may wonder: why only the Chinese chose to build a Great Wall as a form of military defense? Numerous civilizations have flourished in the history of mankind, and there are places other than China large enough to accommodate the Great Wall, but why China? If we understand a bit about the geographic history, we will solve this biggest mystery related to the Great Wall.
If you were a meteorologist, you would be familiar with a fine diagonal line drawn from the northeast to southwest of China. This line is the 400 millimeter precipitation line in northern China. North of this line, the annual rainfall is less than 400 millimeters and it is not ideal for the growth of any crops, and south of this line, the annual rainfall is more than enough to nurture fertile farmland. This line extends across the north China plain to the northwestern part of China along the Silk Road. Due to this natural geographic situation, nomadic civilizations dominated the vast territory north of this line, while land to the south was occupied by Chinese farmers. The nomadic herdsmen lived a very rough life in the ancient times and they frequently had to deal with unforeseeable natural disasters like drought. When the animals died, the nomads would have no other choice, but to ride their horses to loot their farmer neighbors in the south. And when the tribes were unified to be become a powerful nomadic regime, the farmers sought help from their emperors, and the best solution the Chinese rulers gave to this problem, from 5 century B.C. to 16 century A.D. , had always been building a Great Wall.
So the construction of the Great Wall in China is not a matter of coincidence, but rather a rational choice made by the ancestors of the Chinese people.
