It is a single-track standard-gauge and metre-gauge (dual-gauge) line connecting the capital Hanoi to Đồng Đăng, on the China-Vietnam border in Lạng Sơn Province.

The station on the Chinese side of the Friendship Pass is Pingxiang.

The first section from Lạng Sơn to Bắc Giang was built between 1890 and 1894, originally adopting a 600 mm narrow gauge.

Under the rule of governor Paul Doumer the railway was converted to metre gauge and extended to Hanoi (in 1900), and to Đồng Đăng (in 1902).

[6][7] On 1 January 2009 through passenger service between Nanning (China) and Gia Lâm (Hanoi) started.