Great Wall of China Built

The history of the construction of the Great Wall of China can be dated back to the Western Zhou Dynasty (11th century BC - 771 BC). But the Great Wall at that time was only a line of fortresses standing to defend against attacks from the Yanyun (an ancient nomadic tribe in north China). The Period of the Warring States (476 BC - 221 BC) was an era when the seven states (Qi, Chu, Yan, Han, Zhao, Wei, Qin) were busy engaging in Great Wall construction for self-defense. Instead of one line, their walls stretched in the four directions and varied in length from several hundred miles to one or two thousand miles.

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