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The Great Wall of China known to be over 1900 kilometres long , making it by far the longest wall in the world. The building of the wall is said have begun in the third BC . The reason it built was to keep the Huns out of Central Asia. A lot of effort was put construction the wall. It is of earth, stone and brick and its highest section is close to nine meters. Over the centuries, the wall has often added to , rebuilt and repaired. This was done to give China protection invaders. Despite its size, however, the wall failed to a stop to invading armies such as the Mongols and the Manchus.

The wall is still of great importance, as it divides Inner China from Outer China. What is , it is useful for dividing the region into cultivated land and pastureland. The Great Wall holds another impressive record won't be surpassed for quite a while. It is the only man-made structure visible from . It is no wonder that most travel guides refer the great Wall of China as the world's greatest tourist attraction.