What is China wall?

The Great Wall of China, also known simply as the Great Wall, or less commonly as the Ming Great Wall, is a fortification made of stone, brick, tamped earth, wood, and other materials, generally built along an east-to-west line across the historical northern borders of China to protect the Chinese states and empires against the raids and invasions of the various nomadic groups of the Eurasian Steppe. Several walls were built from as early as the 7th century BC, with selective stretches later joined together by Qin Shi Huang, the first Emperor of China (220–206 BC), the Ming dynasty (1368–1644 AD), and other later dynasties.

- Date constructed: 15th-19th Century

- Height: Average of 6-7, Maximum, 39 feet

- Width: At base: 15-30, At parapet; 12-15 feet

- Length: About 21,196 km (13,171 mi)

- Sections: Badaling, Juyongguan, Simatai, Jinshanling, Mutianyu