The Ardrossan Railway was a railway company in Scotland built in the mid-19th century that primarily ran services between Kilwinning and Ardrossan, as well as freight services to and from collieries between Kilwinning and Perceton. The line was later merged with the Glasgow and South Western Railway, and is today part of the Ayrshire Coast Line.
In the first years of the nineteenth century, the 12th Earl of Eglinton developed Ardrossan Harbour, intending it as a sea port for the City of Glasgow. The extensive works he had carried out cost over £100,000. At that time the River Clyde was not navigable to large vessels, and he proposed a canal to reach Ardrossan. In 1806 he obtained Parliamentary authority to construct the Glasgow, Paisley and Ardrossan Canal. The authorised share capital was £140,000, but subscriptions disappointed him, amounting to only £44,342. Work proceeded from the Glasgow end, but the canal only reached Johnstone, all of the available money having been expended and debts of £71,209 incurred.
The truncated canal traded for some years, but in the 1820s the idea was proposed to build a railway to close the gap. An Act for the Ardrossan and Johnstone Railway was obtained on 14 June 1827, the estimate for the work being £94,093; the debt of the canal enterprise was not assumed by the new railway company.
Once again subscriptions fell short of the desired value: they amounted to only £28,950, but work started, from the Ardrossan end, and once again the money was entirely expended, this time with debts of £20,000, after only part of the scheme was built. It reached only from Ardrossan to Kilwinning, but with a long eastward branch that served collieries—most of them part of Eglinton's estate. By now the Clyde had been deepened and sea-going vessels could reach Glasgow. In comparison, even had the railway been completed, it would have required transshipment twice (from ship to railway and from railway to canal), and it was clear that shipping owners would find that unattractive. It is likely that the emphasis had shifted from making the Glasgow connection.