As its name implies, the East West line connects central Singapore to both eastern and western parts of the island, with an additional branch between Changi Airport and Tanah Merah, which operates as a separate shuttle service. Some stations are commonly placed at the middle of the roads such as Tanah Merah, Bedok, Queenstown, Commonwealth, Dover, Clementi, Pioneer, Joo Koon, Gul Circle, Tuas Crescent and Tuas West Road. The line runs mostly on overhead viaducts but goes underground in the city area between Kallang and Redhill, Bedok and Kembangan, and between Expo and Changi Airport. Travelling from one end of the line to the other takes about 78 minutes.