The North China Plain is based on the deposits of the Huang He (Yellow River) and is the largest alluvial plain of eastern Asia. The plain is bordered on the north by the Yanshan Mountains and on the west by the Taihang Mountains. To the south, it merges into the Yangtze Plain. From northeast to southeast, it fronts the Bohai Gulf, the highlands of Shandong Peninsula, and the Yellow Sea. The Yellow River flows through the middle of the plain into Bohai Gulf.
The southern part of the plain is traditionally referred to as the Central Plain which formed the cradle of Chinese civilization.
The plain covers an area of about 409,500 square kilometers (158,000 square miles), most of which is less than (50 m) above sea level. This flat yellow-soil plain is the main area of sorghum, millet, maize, and cotton production in China. Wheat, sesame seed, peanuts and tobacco are also grown here. The plain is one of the most densely populated regions in the world.
Beijing, the national capital, is located on the northeast edge of the plain, with Tianjin, an important industrial city and commercial port, near its northeast coast. Dagang Oilfield in Tianjin and Shengli Oilfield in Shandong are important petroleum bases.
Because the fertile soil of the North China Plain gradually merges with the steppes and deserts of Central Asia, with no natural barriers between the two regions, the plain has been prone to invasion from Central Asia and Manchuria, prompting the construction of the Great Wall of China.
Although the soil of the North China Plain is fertile, the weather is unpredictable, being at the intersection of humid winds from the Pacific and dry winds from the interior. This makes the plain prone to both flood and drought. Finally, the flatness of the plain creates massive flooding when river works are damaged. In the opinion of many historians, these factors have encouraged the development of a centralized Chinese state to manage granaries, maintain hydraulic works, and man fortifications against the steppe peoples.