Ningxia Hui autonomous region is home to segments of the Great Wall dating to different historical periods, including the Warring States period (475-221 BC), the Qin (221-206 BC), Han (206 BC – AD 220), Sui (581-618), Song (960-1279) and Ming (1368-1644) dynasties. The visible length of the remaining wall is 1,038 kilometers. By comparison, Ningxia is 450 km from south to north and about 250 km from east to west.
The sites include rammed earth walls, stone walls, ravines, trenches, mountain ranges, and other dangerous structures. From the early times, Ningxia contained rich resources of the Great Wall that did not quite match its relatively small area, so this region is widely known as the "Museum of the Great Wall of China".
Ningxia had long been a critical northern frontier since ancient times, especially during the Ming Dynasty.Covering 66,400 square kilometers, Ningxia accounts for only 0.69 percent of China's total land area. However, it has two of the nine major border towns along the Ming Great Wall in history. There used to be “Nine Garrisons of the Ming Dynasty”, two of which are located in the Ningxia region today (Garrison of Ningxia and Garrison of Guyuan).
The Great Wall Pass (Changcheng Guan) in Yanchi county is the only pass named after the Great Wall itself among thousands of Great Wall passes of the Ming Dynasty.To the south of the pass lies the ancient city of Huamachi (today's Yanchi county), where during the Ming Dynasty trade between people of the Central Plain and the nomads in the north took place. Horses reared by northern peoples were exchanged for silk, tea, grains, sugar and salt brought by merchants from the Central Plain and southern farming areas. The peace and harmony of these barter markets are guaranteed by the existence of the Great Wall nearby.
Throughout Chinese history, the gates of Changcheng Guan, as well as many other Great Wall passes, blocked only troops. They had remained open to the peaceful and mutually beneficial commercial and cultural exchangesfor the most of the time.