The 2nd Airport Expressway (Chinese: 首都机场第二高速公路), officially numbered S51, is a toll expressway that connects eastern Beijing with Terminal 3 of Beijing Capital International Airport. It opened on February 29, 2008, just prior to the 2008 Beijing Olympics. It runs for 11.5 km from Yaojiayuan Road in Chaoyang District to the terminal.
References
2nd Airport Expressway Wikipedia(Text) CC BY-SA