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The Great Wall of China ‘zig-zags’ central-east Asia and it is an incredible structure. It took over a thousand years to build and is over 1500 miles in length. It is the longest, oldest, most time consuming construction project ever attempted, in history. It is said that the Great Wall can be seen from Earth orbit, although there is some dispute regarding this. It is only when cameras are used, that sections of the wall can be differentiated from the surrounding countryside.

The Great Wall was built for defensive purposes, especially to stop attack from the north of China. Emperors feared that China would be conquered from the north. The Wall stretches across deserts and up and down mountain ranges. 

The Great Wall was part of a Chinese strategy of preventing mass invasion. In the early years the walls were made of rammed earth but as hundreds of years past more sophisticated methods of building were developed with rocks, bricks and mortar being used. It is estimated that over one million people helped in the construction of the Great Wall.

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The construction of the Great Wall of China was apparently one of the major achievements of Chinese civilization, but till the present moment the reasons for the construction of the Wall are still unclear. There exist different versions concerning the creation of the Great Wall of China and its reasons but none of them is absolutely reliable and the arguments concerning this problem persist. Among specialists that were the most successful in the research of the major reasons of the construction of the Great Wall of China may be named Arthur Waldron and Thomas Barfield. Both scientists researched this problem in depth but they view the major reasons of the construction of the Wall in quite a different way, though the position of both scientists in the understanding of this problem is of a paramount importance. The analysis of works by Arthur Waldron and Thomas Barfield shows that while Waldron follows the policy debates under the Ming in detail, his account of these debates and their influence on the building of the Great Wall is insufficient without taking into account the broader issue of Ming fear of the Mongols. Only by emphasizing this fear, as Thomas Barfield does, can we really understand Ming policy.