THE GREAT WALL OF CHINA

https://www.chinahighlights.com/greatwall/

The Great Wall of China covers much of the Northern border of China. The length of the Great Wall was largely built by the Ming Dynasty between the 14th and 17th Centuriesvand is around 8000 kms long; but if the lengths of all the portions of the wall built by every Chinese Dynasty, plus various branches, it would be 21,000  kms long.

The Great wall is an integrated military defensive system with watchtowers for surveillance, fortresses for command posts and logistics, and beacon towers for communication.

• Today, the walls continue to erode, however efforts are being made to protect what sections they can
• The height and width of the wall varies over its length averaging about 10 m tall and 3 m wide. 
• It is the longest man made structure in the world but it is a myth that it can be seen from space and is named as one of the Seven Wonders of the World.
• The wall extends through all sorts of terrain and into the mountains. At its highest point it is 1500 metres above sea level.Wide moats were often dug outside the wall in flat areas.
• Smoke signals were used to indicate an attack.