Thanh Hóa is the capital city of Vietnam's Thanh Hóa Province. The population is more than 197,000 inside an area of 57.9 square kilometers. The city is located south of the Sông Hồng (Pink River) delta region, about 137 km south of Hanoi, on a small tributary of the Mã River (Sông Mã). Thanh Hóa is linked with Hanoi by road and railway and considered to be a growing trade and industrial center. Agriculture, forestry and fishery are being developed here.