Air pollution obscures the view from Coal Hill in central Beijing, China.
 view of air pollution over the CCTV building in Beijing, China.
Air pollution obscures the view of the Forbidden City from Coal Hill in central Beijing, China.
A cyclist passes Tiananmen Square on a heavily polluted day in the capital.
Young men pose for pictures on Coal Hill in central Beijing, China. Air pollution obscures the view of the Forbidden City behind them.