How did they built the Great Wall?

When was the great wall of china built?

• it was first built in 7th century B.C., when china was divided into many small states.After unification of china in 221B.C. the first emperor of Qin Dynasty,linked the walls of the three states in the northand formed the first "Wan li chang cheng"{ten thousand li great wall,li is a chinese lenght unit, 2li = 1km}, since then the great wall was rebuilt,modified or extended throughout chinese history for over 2000 yrs.Most of the great wall we see today was built in the Ming Dynasty {1368 - 1644 }.

• Answer:

  The construction of the wall began during the Spring and Autumn period (770-476 BC) and Warring States period (475-221 BC) during the Eastern Zhou Dynasty. Ducal states at that time built walls to defend their own territories. After the First Emperor of the Qin Dynasty crushed all rival states, he founded the first centralized and unified dynasty in Chinese history. To consolidate the country and ward off invasion by ethnic minority tribes in the north, he had the walls linked and extended, giving rise to the 5,000-kilometer-long Qin Great Wall. Later dynasties from Han (206 BC – AD 220) to Ming (1368-1644) kept building and improving the wall, extending it more than 1,000 kilometers to today‘s scale.