Urbanization is vital to China’s development over the next decade. In fact, the secondary cities will be just as important as the first-tier cities, if not more so, because they will play a key role in fueling China’s inland growth. With a combined population of 43 million, nearly the size of Spain’s, and a combined GDP of $550 billion, which would rank 20th in the world, China’s two flagship cities have often determined the economic fate of the rest of the country. They are also prime examples of the challenges for megacities, such as escalating house prices, traffic gridlock, extensive air and water pollution, and overcrowding.

http://www.china.org.cn/opinion/2013-11/12/content_30571683.htm

“Concerns for secondary cities” China Daily (Beijing), 12 Nov 2013, with Asit K. Biswas, p. 9.