which chinese dynasty did the most work on the great wall
History of the Great Wall of China Later dynasties adopted different policies towards northern frontier defense. The Han (202 BC – 220 AD), the Northern Qi (550–574), the Sui (589–618), and particularly the Ming (1369–1644) were among those that rebuilt, re-manned, and expanded the Walls, although they rarely followed Qin's routes. The Han extended the fortifications furthest to the west, the Qi built about 1,600 kilometres (990 mi) of new walls, while the Sui mobilised over a million men in their wall-building efforts. Conversely, the Tang (618–907), the Song (960–1279), the Yuan (1271–1368), and the Qing (1644–1911) mostly did not build frontier walls, instead opting for other solutions to the Inner Asian threat like military campaigning and diplomacy.