Beijing formerly romanized as Peking is the capital of the People's Republic of China and one of the most populous cities in the world, with a population of 19,612,368 as of 2010. The metropolis, located in northern China, is governed as a direct-controlled municipality under the national government, with 14 urban and suburban districts and two rural counties. Beijing is China's second largest city by urban population. Beijing is a major transportation hub in the national highway, expressway, railway and high-speed rail network. Beijing is one of the Four Great Ancient Capitals of China.