During
770-476 BC, a large wall was built to protect Chinese empire from the attacks
by the nomadic tribes in the north. Today, the Great Wall of China is as long
as 12,000 kilometers. It starts from the Bohai sea in the East and ends at Lop
Nor in the West. It also passes through the Gobi Desert. The whole wall was
constructed using stones, earthen fortifications and bricks....
