A princess once garrisoned the pass

Niangziguan, located in Pingding County, Shanxi Province, is located at the junction of Jin and Ji in the middle section of the Taihang Mountains and is a key cultural relics protection unit. Niangziguan, known as the ninth pass of the Great Wall, is a battleground for the military in all ages. The pass was built by the team stationed by Li Xiuning, the Princess of Pingyang, the daughter of Li Yuan. Princess Pingyang was the first princess of the Tang Dynasty to have a posthumous title after her death. The discipline of Niangzi was strict, the orders were carried out, the people were not disturbed, and she was supported by the masses. The team led by Princess Pingyang was called "Niangzi" by the common people, so the pass where they were stationed was naturally called "Niangziguan".