Pathum Wan District
It runs eastward from the National Stadium Station in Pathum Wan District over Rama I Road and interchanges with the Sukhumvit line at Siam BTS station, then turns southward, following Ratchadamri, Si Lom, Narathiwat Ratchanakharin and Sathon Roads to Taksin Bridge where it crosses the Chao Phraya River to the Thonburi side of Bangkok and Wong Wian Yai. It continues west along the Ratchapruek rd corridor before it terminates at Bang Wa Station in Phasi Charoen District.