Explanation

Who Built the Great Wall?

Qin Shi Huang, also called the First Emperor, united China.

Chinese created this wall as a defense against?

Mongols

When great wall of china was made ?

221 BC (7th CE)

The Ming Great Wall's Length:

8,851 km (5,500 mi)

The official length of the Great Wall is

21,196 km (13,170 mi).