Qin Dynasty (221-206 BC)

Apart from the Yinshan section to the north, the Qin Great Wall was primarily constructed by integrating the fortifications of the Warring States period belonging to the states of Qin, Zhao, and Yan into a continuous wall. The Qin Great Wall, built by Emperor Qin Shi Huang, stretches from Lintao in the west to Liaodong in the east. This construction made it the first Great Wall with a total length exceeding 5,000 kilometers, hence it is called the "Great Wall of 10,000 Li."