The Main Suburban railway line is the technical name for the trunk railway line between Redfern railway station and Parramatta railway station in Sydney, Australia, but now generally refers to the section between Redfern and where the Old Main South Line branches off at Granville Junction. The railway line then continues on as the Main Western line towards the Blue Mountains. This term distinguished this trunk line from the Illawarra Line which branched south from the Illawarra Junction to Wollongong, and later the North Shore tracks which carried trains north over the Harbour Bridge.