guangzhou metro line two, the representative color is blue. the first section ( sanyuanli - xiaogang ) in december 29, 2002 began trial operation. in june 28, 2003, metro line two sanyuanli - pazhou segment began formal operation. line two uses a lot of domestic and international are leading technology. guangzhou subway line two is the world all built before installing platform screen door subway line one. shielding door can ensure the safety of passengers, but also can save the