Kuala Lumpur KLIA Aerotrain Bombardier CITYFLO 550 Qatar Doha Metro all lines 2019 Thales CBTC Saudi Arabia Riyadh Metro Blue Line, Red Line 2019 Siemens CBTC Orange Line Ansaldo STS Yellow Line, Green Line, Purple Line Alstom Urbalis 400 Singapore Light Rail Transit (Singapore) Bukit Panjang LRT line 6 November 1999 Bombardier CITYFLO 550 Sengkang LRT line 18 January 2003 Kyosan APM Punggol LRT line 29 January 2005 Changi Airport Skytrain 2006 [lower-alpha 2] Mass Rapid Transit (Singapore) North East MRT line 20 June 2003 Alstom Urbalis 300 The largest fully automated rapid transit network in the world with 199 km (124 mi) of automated rail lines.[9] Trains may have an attendant on board.