S1 Expressway (Thailand)

The S1 Expressway (ทางพิเศษสาย S1), also known as the Bang Na–At Narong Expressway (ทางพิเศษสายบางนา–อาจณรงค์), is an expressway in Thailand, located in Bangkok. It is 4.7 kilometres in length. The expressway is a controlled-access toll road.

History
The S1 Expressway was opened on 15 June 2005 to provide an elevated road connection between the Chaloem Maha Nakhon and Chalong Rat Expressways to the Buraphi Withi Expressway. It has a single toll plaza, the Bang Chak toll plaza, for cars travelling from the S1 onto the Chaloem Maha Nakhon. Cars can travel to and from the Chalong Rat with no intermediate toll plaza (pay at exit).