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| Archive > September 2009, Volume 23, Issue 9 > The Greater Wall of China |
The Greater Wall of China11/08/2009 |
| A study conducted by the Chinese State Administration of Cultural Heritage and the Chinese State Bureau of Surveying and Mapping in thirteen provinces, regions and municipalities, has revealed no less then 3,850km of unknown sections of the Great Wall or, as the Chinese name it, the ‘Long Wall of 10,000 Li'. |
| Henk Key, contributing editor, GIM International |
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Until now the length was commonly put at about 5,000km, but the two-year government mapping study found that the wall spans 8,850km. The project found ‘new' wall sections of 6,259km, 359km of trenches, and 2,232km of natural defensive barriers such as hills and rivers.
Infra-red, satellite, and aerial photographs were used to locate supposed locations, ground-penetrating radar helped locate areas concealed over time by sandstorms, and GNSS systems were used to map all the discoveries.
The construction of the wall, the world's largest manmade structure, began in the fifth century BC, when it was built to protect the northern border of the Chinese Empire. It has been listed as a Unesco world heritage site since 1987. (Source: BBC)
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The newly-discovered sections of the wall were built during the Ming Dynasty and stretch from Hu Mountain in northern Liaoning province to Jiayu Pass in western Gansu province. The study will continue in order to map sections of the wall built during the Qin (221-206BC) and Han (206BC-9AD) Dynasties.
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