Since China's reform and opening-up in 1978, China has broken boundaries among different administrative regions to form a number of closely-knit economic rims or belts, most notably, Pearl River Delta, Yangtze River Delta and the Bohai Rim. These urban agglomerations, each centering on a core megacity, have become massive powerhouses for the country's rapid economic development. They have also simultaneously spurred the development of their surrounding areas. In the coming decades, they will remain the most dynamic economic regions in China. China is constructing additional economic rims with city clusters at their core to promote coordinated regional development.
