extensive low-lying area formed by the junction of the Xi (Xi River system), Bei (Bei River), Dong, and Pearl (Zhu) rivers in southern Guangdong province, China. It covers an area of 2,900 square miles (7,500 square km) and stretches from the city of Guangzhou (Canton) (Canton) in the north to the Macau Special Administrative Region in the south. The delta is a maze of streams and canals between small rice paddies that, because of the 12-month growing season, commonly support three rice crops annually. It is one of the most crowded areas of China, where modern industry and agriculture have been rapidly developed since the 1980s.