Great Wall, The

(of China) a fortified wall in northern China, an immense architectural monument of ancient China.

The first sections of the Great Wall were raised during the fourth and third centuries B.C. After the unification of China in 221 B.C., the emperor Ch’in Shih Huang-ti ordered the construction of a continuous solid wall in order to protect the northwestern borders of the empire from attacks by nomadic peoples. In later times the Great Wall was kept in constant repair and new sections were repeatedly added. The wall stretched from east to west, beginning at the city of Shanhaikuan on the coast of the Liaotung Bay and ending at Chuichuan in Kansu Province. The length of the Great Wall, according to some estimates, does not exceed 4,000 km, while others believe it to be greater than 5,000 km. The height is 6.6 m (up to 10 m in some sections). The width of the lower part is approximately 6.5 m, and the width of the upper part is approximately 5.5 m. Watchtowers and casements for protection are constructed along the entire length of the Great Wall, and forts are located at the chief mountain passes. Much of the Great Wall remains standing today.