Ải Nam Quan
Friendship Pass (traditional Chinese: 友誼關; simplified Chinese: 友谊关; pinyin: Yǒuyì Guān; Cantonese Jyutping: Jau5 Ji4 Gwaan1; Cantonese Yale: Yau5 Yi4 Gwaan1; Vietnamese: Hữu Nghị Quan), also commonly known by its older name Ải Nam Quan (隘南關), is a pass near the border between China's Guangxi and Vietnam's Lạng Sơn Province, on the Chinese side of the border (21°58′35″N 106°42′44″E / 21.97639°N 106.71222°E). Vietnamese National Route 1A starts near to this pass, which lies less than 5 km north of the town of Đồng Đăng in Lạng Sơn Province, ending in Năm Căn in Cà Mau Province. China National Highway 322 runs from here to Guangxi Province and Hunan Province. This is one of the busiest border trading points of Vietnam.
It was built in the early Ming dynasty with the name of "South Suppressing Pass" (traditional Chinese: 鎮南關; ; pinyin: Zhèn Nán Guān; Cantonese Yale: Jan3 Naam4 Gwaan1; Vietnamese: Trấn Nam Quan). In 1953, its name was changed to "South Watching Pass" (traditional Chinese: 睦南關; simplified Chinese: 睦南关; pinyin: Mù Nán Guān; Cantonese Yale: Muk6 Naam4 Gwaan1; Vietnamese: Mục Nam Quan). In 1965, its name was changed again to the current Friendship Pass, reflecting the close political, military, and economic ties between the People's Republic of China and North Vietnam during the then-ongoing Vietnam War.
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Wikipedia