This year saw China's urban population exceed its rural population for the first time ever, as economic growth in the country's booming southern and eastern seaboards continues to lure migrants from China's rural heartland. Today, more than 160 cities in China have a population of over 1 million, compared with nine in the United States. The steady mass migration over the past decade has meant tremendous social upheaval: traditional architecture demolished to make way for tower blocks, cities running out of water, and millions of migrants who -- because of the way China's safety net is structured -- don't have access to social services outside of their hometowns. So far, central government reform proposals to give more services to migrant workers and their families have met with fierce resistance from some local governments and urban residents, but the urbanization trend shows few signs of stopping.
Above, migrant workers arrive at a bus station in Beijing in July 2011.
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