The Elevated Train in Commemoration of HM the King's 6th Cycle Birthday First line (Sukhumvit) or Sukhumvit line (Thai: รถไฟฟ้าบีทีเอส สายสุขุมวิท) is an elevated metro rail line of the BTS Skytrain in Bangkok, Thailand. From the central Siam Station, where it connects with the Silom Line, the line runs both northwards along Phaya Thai and Phahon Yothin Roads to Mo Chit station in Chatuchak District, and eastwards along Rama I, Phloen Chit and Sukhumvit Roads, through Bang Na District to Kheha Station in Samut Prakan.