Han Dynasty (206 BC-AD 220)

The Han Dynasty inherited the Qin system. Emperor Gaozu of the Han repaired the old fortifications of the Qin. Later, to fight against the Xiongnu nomads in the north, Emperor Wudi constructed a Great Wall that spanned from Liaodong in the east to Xinjiang in the west. Notably, the Han Great Wall is the longest in history, extending for a total length of over 10,000 kilometers.