Thái Nguyên is a province in northeastern Vietnam. It is a mountainous, midland province represented by eight ethnic groups. Thái Nguyên borders five provinces: Bac Kan to the north, Vinh Phuc and Tuyen Quang to the west, and Lang Son and Bac Giang to the east. Thái Nguyên also borders the Vietnamese capital of Hanoi to the south. Thái Nguyên is the gateway for socio-economic exchange with the Red River delta. The exchange is carried out via road, rail and waterways in the province. Main water features include the Cong River and Nui Coc Lake. The province is also the centre of tea industry in the country with an area of 16,000 ha (second only to Lam Dong).