The Light Red Line is part of the planned Red Line suburban railway system to serve the Bangkok Metropolitan Region. It will run east–west from Sala Ya in Phutthamonthon District of Nakhon Pathom Province to Hua Mak in Bangkok. The segment from Taling Chan to Bang Son (15 km) opened for limited, free trial service on December 5, 2012. Only 12 services a day (6 each way) operated on the line until all services were fully suspended on 13 January 2014 pending further notice.