The site of the southern border defense fortress built in the Ming and Qing Dynasties of Guangxi Zhuang Autonomous Region. The most famous border customs friendship gate is located between Nanda Qingshan and Jinjiling in Pingxiang City, adjacent to Vietnam to the south, and is the throat of China-Vietnam traffic. Friendship gate formerly known town Nanguan, one of the nine famous gates in China. It has been renamed Mu Nanguan and Friendship Guan. It is now a national cultural relics protection unit, but there are not many tourists.