NEW YORK, Sept 19 — The Great Wall of China is a 13,000-mile (20,921km) dragon of earth and stone that winds its way through the countryside of China.
The Great Wall started as a series of smaller walls of ramped earth built by various feudal states during the Chunqiu period around 771 to 476 BC.
The walls were connected and fortified by emperor Qin Shih Huang when he united the feudal states into what would become the basis of modern China.
The walls served as protection against the Turks, Mongols and other powers who seek to conquer China.
Over the years, China expanded beyond the Great Wall, making it obsolete, and it fell into disrepair.
Megan Campisi and Pen-Pen Chen detail the building and subsequent decay of this massive, impressive wall in this Ted-Ed video.
