Friendship Pass , 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 . 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.