太原省
Two railway lines serve Thái Nguyên Province, and particularly the city of Thái Nguyên. The first line connects Hanoi Railway Station to Quán Triều Railway Station (Quán Triều Ward), and the second connects Lưu Xá Railway Station (Phú Xá Ward) to Hạ Long Railway Station, Hạ Long, via a railway junction at Kép in Bắc Giang Province. Both lines were built after the First Indochina War; unlike most railway lines in Vietnam, which were established in metre gauge, the Luu Xa–Hạ Long line was built at standard gauge, and the Hanoi–Quán Triều line was built at mixed gauge. The rail spur connecting Luu Xa and Kép was a strategic line constructed between October 1965 and December 1966 by a railroad engineering division of the Chinese People's Liberation Army, who operated in North Vietnam repairing railway lines at the request of Ho Chi Minh.