The Great Wall of China: why there is not one date of construction

Useful to know

The Great Wall of China unites fortification lines from different periods. Around 220 BC, earlier fortifications were connected at Qing, and construction and development continued during the Ming period. [1]

A picture of one section does not automatically represent the material and type of the whole system. When comparing parts, check their location and period. Long historical use includes alterations and redevelopment. It is more accurate to speak of a system of lines and stages than of a single wall built at once by a single ruler.