The junction with the Edinburgh and Glasgow Railway at Greenhill gave satisfactory access for Scottish Central trains to Glasgow Queen Street, but was inconvenient for Edinburgh. In the 1846 Parliamentary session, the E&GR submitted a Bill for the Stirlingshire Midland Junction Railway, which was to build from Polmont to a junction near Larbert, giving a direct connection.
The Greenhill junction provided convenient access for Scottish Central trains to Glasgow Queen Street, but was inconvenient for Edinburgh. In 1846, the Edinburgh and Glasgow Railway (E&GR) proposed a bill for a new railway line from Polmont to a junction near Larbert to provide direct connection.