Chengdu Urban Railway Line S3 is aline connecting Tianfu International Airport and downtown Ziyang, starting from Futian Station of Chengdu Metro Line 18 and ending at Ziyang North High Speed Railway Station in Ziyang City. The total length of the line is about 39.37 kilometres, the roadbed section is about 3.91 kilometres long, and there are a total of 7 stations on the express line, including 3 elevated stations and 4 underground stations. It is the first urban rail transit line in Sichuan Province, and also the first cross-city operation train debut in the field of rail transit of Chengdu, Demei, Ziyang, forming one hour commuting circle by rail transit.