|Nineteen walls have been built that were called the Great Wall of China||The length of the Great Wall of China is estimated to be about two thousand and four hundred kilometers|
|The most well-known sections of the wall were built by Ming Dynasty||It took more than 2000 years for building and completion of the Great wall|
McGregor, Richard 2 July 2007.
|International Monetary Fund April 2008||Jin, Fan, and Liu 1996 , 178—179; Needham 1972 , 111|
|Retrieved on 27 July 2008||The Great Wall of China crosses many of the great geographical terrain, such as mountains, mountains, rivers and meadows|
After the unification of China in 2324, the construction of the wall increased, Over 300 thousand Chinese workers built it,and the wall has undergone improvements and developments over successive years.3