The northern end of the proposed system was a junction to another railway at Whifflet, and perhaps did not seem an attractive component when the company's name was being chosen.

Priestley says that the line was "designed to pass from the collieries of Chapel and Crawfoot, in the parish of Cambusnethan, in the county of Lanark, through Daiziel, Hamilton, Bothwell, Coltness, Overtown, Wishawtown, Motherwell, Burnhouse and Carnbroe, to join the Monkland and Kirkintilloch Railway at Old Monkland; with a branch to Rosehall; a second to the collieries of Stevenson, Carfin and Cleland; and a third from these last places to Law, in the parish of Carluke, in the same county of Lanark".

As far as this point, the route is still in operation today as Whifflet - Mossend North Jn - Holytown - Carfin, but here the original line turned south to serve several pits in the Cleland estate at Chapelknowe.

[10] In 1836 Thomas Houldsworth, a Manchester entrepreneur, purchased the Coltness Estate, with its extensive mineral rights.

He also agree to give the necessary land on the Coltness Estate free (apart from compensation to tenants) and to send all his goods by the railway, if the Company charged him the prevailing rate."

The location was at the north end of the (later) Ravenscraig complex, and the route was to the east of the present Mossend - Motherwell line (opened in 1857).

[10] In 1842 a further extension was opened, taking the line on from Coltness Colliery to Chapel Colliery—the first-named objective in Priestley's description[6]—in the area of Morningside.

[10] The final stage in the gradual extension of the route was achieved on 9 March 1844;[9] continuing from Chapel Colliery, the line ran the short distance to pits and a brick and tile works close to Morningside, involving a bridge over the Auchter Water.

The newcomer was always short of money and never succeeded to connecting the important iron works at Wilsontown, and the Inspecting Officer for passenger operation wrote that "the line terminates in a large field, about a mile from a small village called Whitburn.

[14] In 1839 the company decided to adopt locomotive traction, and to reduce the multiplicity of horse traders, in order to "do away with the collisions which are daily taking place between the drivers".

It was reported that When received, they were forthwith applied to the purpose of the traffic, and they have provided the advantages to be derived on this as on the adjoining railways from the more general employment of engines instead of horse haulage.

When the Caledonian Railway built a new line via Newmains, it approached Morningside from the north and a passenger service from Holytown terminated there.

[20][21] The line was built as a coal railway, with the primary object of conveying the mineral to market in central Scotland.

The industrial processes developed rapidly during the first decade of the line's existence, so did the demand for efficient transport.

As the Coltness Iron Works and other industries developed, they needed to bring in materials from further afield, and to dispatch their products to far-off destinations.

Parts of the Wishaw and Coltness routes remain in use at the present day: the section from the original Motherwell station, just south-east of the present-day station, to Garriongill Junction, and the section from Whifflet to Mossend South Junction follows the original construction.