北京. Variously romanised as Beijing (pronounced bay-jing and not
beige-ing) or Peking (the older form, originally adopted by French missionaries four hundred years ago) in English, it's the capital of the People's Republic of China
. The name literally means 'Northern Capital'—China having gone through a fair number of capital cities in its history, for instance Nanjing/Nanking meaning 'Southern Capital'. Roughly 20% of the people in the world at any one time have been ruled from this city for centuries, which is a little scary, when you think about it.
This trope's name for the city references the Katie Melua song "Nine Million Bicycles", and is based on the fact that traffic jams with bicycles used to occur in the streets (it's still probably one of the few cities on Earth were the bike lane can take up half the street). The bikes have been replaced by myriads of cars these days, along with lots of air pollution and thick smog.
The population of this Mega City
is roughly 17.43 million, based on those who live there six or more months a year (you need a residency permit to live in Beijing). By rich-country standards, the pollution in Beijing is very bad. By developing-country standards, the air quality in Beijing is not exceptional, being rated "only" 13th worst in the world in 2004 by the World Bank.
It hosted the Olympic Games
in 2008, which provoked massive controversy, particularly with regard to China's human rights violations and Tibet
北京 in fiction