Guangzhou has Baiyun Airport, which is one of the three most important parts of air transportation in the country. The passenger throughput ranks third in China and 19th in the world. It is also a very important harbor in China, second to Shenzhen in South China and the fourth one in the country. With the Jing-Guang Railway, Jing-Jiu Railway, Guang-Shen Railway and other railways, Guangzhou has become one of the four biggest railway passenger stations in China. A high speed railway has been built here.