What is the history of Mutianyu Great Wall?

Mutianyu was originally a small mountain village, located in Beixinying Township, Huairou District (now Bohai Town), where the mountains are undulating and the trees are lush. The Great Wall of Wan Li winds from southeast to northwest at the top of the mountain. The mountains here are gentle and steep, and the curves and straights alternate, so it is very stereoscopic. Mutianyu is known as the "Xiongguan of Dangerous Ridge" because of its very important geographical position, and Mutianyu Pass is one of the important passes for the Ming Dynasty to support the capital, and it is also the location of the Ming Dynasty's ancestral mausoleum, and there have been many wars. Mutianyu Great Wall connects Juyongguan in the west and Gubeikou in the east, which is the eastern section of huanghua town, the north gate of Beijing. Mutianyu Great Wall has been called the northern barrier to guard the capital and the imperial tomb since ancient times, and Mutianyu Pass is one of the important passes to support the capital and the imperial tomb in Ming Dynasty. (Chang 'an Hakka, Volume 7, Guan Zhen Magazine)

In the Northern Qi Dynasty (550-577 AD) during the Southern and Northern Dynasties in China, the Great Wall was built in Mutianyu and rebuilt in the early Ming Dynasty. According to literature research, Mutianyu Great Wall was built under the supervision of Xu Da, a general of Zhu Yuanzhang in the early Ming Dynasty (once named Zhongshan King, also known as Zhongshan) on the site of the Great Wall in Beiqi. (Records of Gan 'an County in the 12th year of Tongzhi recorded: "At the beginning of the Ming Dynasty, Xu Zhongshan built a side wall, covering an area of more than 1,700 miles from Shanhaiguan West to Mutianyu, with strict border defense." )

Tian Mu Guan Yu was built in 1404 (the second year of Yongle in Ming Dynasty). (See Textual Research on Old News of Sun, Boundary Barrier, Vol. 153, p. 2466. )

In A.D. 1569 (the third year of Qin Long), Qi Jiguang, a famous anti-Japanese ambassador of the Ming Dynasty, led an army to renovate the 2,000-mile Great Wall, including Mutianyu section, and the commander-in-chief learned about the military training in Jizhen, Changzhen and Baoding towns. The ruins of Qin Long in the autumn of five years have been built to 20 13, and the Great Wall preserved and restored in Mutianyu is the best preserved section in the Ming Dynasty.