Why and when was The Great Wall of China built, how high and how wide is it?
The history of the Great Wall is said to start from the Spring and Autumn Periods when seven powerful states appeared at the same time. In order to defend themselves, they all built walls and stationed troops on the borders. At that time, the total length of the wall had already reached 3,107 miles, belonging to different states. In 221 BC, the Emperor Qin absorbed the other six states and set up the first unified kingdom in Chinese history. In order to strengthen his newly born authority and defend the Huns in the north, he ordered connecting the walls once built by the other states as well as adding some sections of his own. Thus was formed the long Qin’s wall which started from the east of today’s Liaoning Province and ended at Lintao, Gansu Province. In the Western Han Dynasty, the Huns became more powerful. The Han court started to build more walls on a larger scale in order to consolidate the frontier. In the west, the wall along the Hexi corridor, Yumenguan Pass, and Yangguan Pa
