The line has its origins in the ambitions of Hugh Montgomerie, 12th Earl of Eglinton, who had headed and championed both the Glasgow, Paisley and Johnstone Canal and the Ardrossan Railway.

On 10 January 1983, the line between Elderslie and Kilmacolm closed completely to scheduled passenger services; but the section between Hawkhead and Shields Junction remained open to serve an oil depot.

While work did commence on the canal at the Glasgow end; it had only reached Johnstone by the time by which all of the raised money for the endeavour had been spent; in addition, the company had also borrowed considerable sums, when combined, debts of £71,209 had been accumulated.

This too was built with the aim of connecting Ardrossan to Glasgow and, just as its predecessor had, it ran out of money during construction, having only reached Kilwinning and Eglinton's collieries in the vicinity.

This lack of sovereignty was a difficult enough prospect for the highly competitive railway politics of the era; but, as traffic developed, congestion on the busy line became a serious and obstructing issue which fuelled conflict.

[citation needed] During the 1881 parliamentary session, a bill was lodged by the G&SWR for the draining of the canal and conversion work to build a railway on its route: exactly the scheme to which the former chairman had described as perfect nonsense only two years beforehand.

[citation needed] During 1881, the same year as the canal's conversion work been authorised by Parliament, it was permanently closed to traffic and drained in preparation for building the railway on top of its former route.

[5] The canal had been built as a contour line, following exactly a particular altitude; in this manner, it had avoided the use of locks at the expense of having to adopt a circuitous route between its destinations.

During the reconstruction works, many of the loops and sharper turns which had been taken by the course of the canal were eased, often via the use of earthworks, as the higher-speed railway was less tolerant of sharp curves but more able to accommodate the presence of mild gradients.

[1][page needed] During the following year, on 5 February 1886, the Potterhill branch of the Canal line opened; this was built to account for the expanding industrial importance of Paisley.

During 1894–1895, construction work on the Canal line was focused upon the building of extensive carriage sidings at Bellahouston, as well as an engine shed at nearby Corkerhill.

The availability of affordable land at these locations had rendered such schemes much more economical, but came at the expense of additional empty mileage.

The line terminated at a station at North Johnstone, however another junction near Elderslie provided access onto the Bridge of Weir Railway.

It had to be widened in order to carry the double track railway, the line also crosses the bridge at a slight skew because of the easing of the sharp canal curvature.

Well, some of the "Heid Yins" were going down to Turnberry Hotel for the weekend, and they were travelling in the Directors' Saloon, a vehicle which Mr. C Hamilton Ellis once described as of "more than imperial splendour".

Right out at the cow's tail and getting all the wag, the distinguished party had a pretty stormy trip all the way to Ayr, at which point the murder of Coutts was strongly advocated.

During the line's latter years, as a cost reduction exercise, the signal boxes were only single-shift staffed, resulting in the last train of the day being run around 7pm.

There were also occasional passenger train diversions away from Paisley Gilmour Street due to works associated with the AyrLine electrification project.

Much of the abandoned railway line beyond the original Paisley Canal station has since been developed into a cycleway and walkway operated by Sustrans.

As the high costs of a conventional approach was judged to be around twice that of which could be justified by the business case, innovative measures and compromises alike were adopted for the planned electrification work.

[5] According to Shirres, a policy of closer working relationships between national infrastructure maintainer and owner Network Rail and franchise operators, in this case ScotRail, had the benefit of significantly reducing the cost of the line's electrification.

Observing that only EMUs were intended to operate the route, Network Rail developed customised overhead line equipment (OLE) for the electrification scheme; according to Brian Sweeney, Network Rail asset engineer for electrification in Scotland, traditional practices were overturned where realistic and the lowest possible wire height for EMU operation was specified, however, the pre-electrification W7 gauge was retained for the line.

[5] In June 2012, Babcock International was awarded a fixed-price design and construct contract to perform all Paisley Canal electrification works with a six-month programme.