Song Hong, the Red River, is northern Vietnam’s largest river. It rises in China’s Yunnan province and flows 1,175 km southeast through deep, narrow gorges to enter Vietnam and discharge into the Gulf of Tonkin via a great delta. The silt it carries is rich in iron oxide, making its water red and giving it its name. The Red River delta is about 120 km long and 140km wide, and is expanding an astonishing 100 meters a year. It is the economic center of northern Vietnam – Haiphong, Vietnam’s main port, lies on a branch of the delta.
The volume of water flowing down the river averages 500 million cubic meters per second, but may increase by more than 60 times at the peak of the rainy season. The smooth Red River clay has created a large pottery and ceramic industryThe entire delta region is no more than three metres above sea level, and much of it is one metre or less. The area is subject to frequent flooding: at some places the high-water mark is fourteen metres above the surrounding countryside. Dikes and canals protect the delta from the floodwaters. A major highway crosses the delta and the coastal strip beyond, an important transportation route linking China and Vietnam. Today, around fifteen million people inhabit the area, one of the highest population densities in the world. Rice is the principal crop of the delta, but wheat, beans, rapeseed, corn, and subtropical crops are also grown.
The historic Long Bien bridge crosses the Red River at Hanoi. Historically, the delta has produced a large number of skilled craftspeople. The annual rice-growing cycle featured a period where farmers left the land fallow, thus freeing them to pursue other money-making ventures. Villages specialized in a wide variety of crafts that ranged from the making of conical ‘non’ hats to the production of lacquer ware. The tradition continues to the present day in the form of Vietnam’s famous ‘craft villages’, mostly clustered in the rural areas surrounding Hanoi and now major tourist attraction.