Caledonian main line
The Caledonian Railway main line in Scotland connected Glasgow and Edinburgh with Carlisle, via Carstairs and Beattock.
The approach to Glasgow used railways already built, primarily for mineral traffic; these were later by-passed by a more direct route.
Today, the route forms the northern section of the West Coast Main Line, and was electrified in the early 1970s.
The line ran broadly north across gently undulating country at first, crossing the River Esk and entering Scotland near Gretna, then climbing following the Kirtle Water to Lockerbie.
Now turning north-west, the Glasgow line continues past Lanark and near Carluke, joining the Wishaw and Coltness Railway (W&CR) at Garriongill Junction.
It turned north through to Whifflat (now spelt Whifflet), joining the Glasgow, Garnkirk and Coatbridge Railway (GG&CR).
From Whifflat the line ran to Coatbridge, and then turned west on through Garnkirk, terminating at the GG&CR Glasgow terminus at Townhead.
The Clydesdale Junction route now forms the northern end of the modern Caledonian main line, extended from South Side to cross the River Clyde to Glasgow Central Station.
[2][3] The Edinburgh section of the Caledonian main line left Carstairs station and ran north-east.
The line continued past Cobbinshaw and Kirknewton, descending into Edinburgh in the valley of the Water of Leith.
[2] The main line as planned was hoped to be the sole connection between Scottish cities and the English network.
In its early years the Caledonian Railway sought to become dominant in large areas of Scotland by leasing nascent companies.
It was able to do so by guaranteeing lease payments in perpetuity, which avoided any need for cash at the time, but heavily indebted the company later.
As the company matured, it encouraged local promoters to start construction of branch lines, taking them over by purchase if they were successful.
These factors led to a limited number of intermediate stations on the main line, and a concentration of effort elsewhere.
This gave it access from Lockerbie to Stranraer and Portpatrick, enabling it to develop ferry services to the north of Ireland.
Mineral extraction in Cumberland around Workington developed considerably, and much of the output went to the Lanarkshire iron works over the Caledonian main line.
From the outset, the rival Glasgow and South Western Railway had intended to build an independent line to Carlisle from Gretna, but this was forbidden by Parliament during the authorisation process.
It was enhanced by subsequent improvement of the route into Glasgow, as well as extension of the Edinburgh terminal named Princes Street, completed in 1870 and the expansion of goods facilities in Carlisle.
The goods by-pass lines at Carlisle became very extensive and were jointly owned and operated by several railway companies.
The principal subsequent developments were: In 1850, the passenger service on the main line consisted of five trains daily from Carlisle to Glasgow, of which three were expresses.
Trains from Liverpool and Manchester combined at Preston and divided again at Carstairs, giving through journeys to Glasgow and Edinburgh.
The original main line was selected as the optimum route through challenging terrain with a very limited population density, and there was little opportunity to deviate to serve intermediate towns and villages.
While some consolidation took place, the basic passenger train service pattern remained relatively unaltered for many years, indeed into the post-1948 era of nationalisation under British Railways.
The Glasgow south side suburban service had been electrified by British Railways from 27 May 1962, when the Cathcart Circle, and Newton - Uddingston - Motherwell were operated electrically.
Further electrification of the Hamilton circle, and to Lanark, followed and the main line southwards was being progressively wired, so that by the end of 1973 electric locomotives could be exchanged between Carlisle and Shields Depot, running for the time being via Kirkhill.
The route is now the northern section of the West Coast Main Line, and carries a heavy passenger and freight service.
At the present day the main line has a heavy long-distance passenger service to London, Birmingham and Manchester.
When the main line was conceived, there were misgivings about the capacity of the locomotive power of the day to handle trains over the heavy gradients approaching Beattock summit.
