Great Wall of China

Pictures of the Great Wall - China

Short history of the Wall 

Actually made of more than one wall, construction of the Great Wall first started in the 7th century B.C, for  defence purposes. After the state of Qin unified China in 221 B.C., it joined the walls to hold off the invaders from the Xiongnu tribes in the north and extended them to more than 5,000 kilometers. 

The Great Wall was renovated from time to time after the Qin Dynasty. A major renovation started with the founding of the Ming Dynasty in 1368, and took 200 years to complete. The wall we see today is almost exactly the result of this effort. With a total length of over 6,000 kilometers, it extends to the jiayu Pass in Gansu Province in the west and to the mouth of the Yalu River in Liaoning Province in the east. What lies north of Beijing is but a small section of it.
(source: www.chinavista.com/)