The first proposals for a railway to Aberdeen were put forward in 1827 when Robert Stevenson was commissioned to assess the potential; however nothing progressed from his study.
The continuous debate in the preceding years had encouraged thoughts of a Scottish network too; this was further facilitated by easy availability of investment money, and the idea of promoting a railway costing hundreds of thousands of pounds seemed suddenly commonplace.
Already in existence was the Arbroath and Forfar Railway, on a broadly west to east axis, and with the distinctive track gauge of 5 ft 6in (1,676 mm).
The directors of the Caledonian Railway had a strategic vision, and they saw that securing territory to their own company was critical; they set about committing independent lines to an alliance with themselves, by leasing them.
This arrangement was made with the SCR and the SMJR, giving the Caledonian control of a continuous railway from Carlisle to Forfar, and access to Aberdeen.
The authorised capital was £830,000 and the Act was given the Royal Assent on 31 July 1845, the same day as the Caledonian Railway and the SCR and the SMJR.
The Aberdeen Railway proceeded with constructing its line, and on 1 February 1848 it opened from the junctions with the A&FR to Montrose and Brechin.
Both were on branches, with Brechin served from Bridge of Dun, and Montrose from Dubton, which was the northernmost point on the authorised main line at the time, and not a destination of great importance.
A Mr Cloudsley operated a horse bus connection until the proper terminus opened on 8 Feb 1850.
A shareholders' meeting in October 1848 considered some radical proposals, including a takeover by the English London and North Western Railway.
On 30 October 1848 the line was extended to Limpet Mill, north of Stonehaven, and it reached Portlethen on 13 December 1849.
[note 2][2][8][9] This involved bridging the River Dee: a laminated timber design was used, but this proved not to be durable and was reconstructed in the 1880s.
In fact the majority of the Aberdeen Railway traffic took the Guthrie curve and ran to Perth via Forfar and the SMJR.
At the same time the rival North British Railway developed its route through Edinburgh and Dundee to Aberdeen; the final approach was over Caledonian tracks by the running powers granted by Parliament.
However passenger and goods traffic was declining, and in the mid 1960s it was becoming obvious that two competing routes to Aberdeen were not sustainable.
On 12 August 2020, a derailment occurred near the site of the former Carmont railway station; three people - the driver, a conductor and a passenger - were killed.
Jowett's Railway Atlas of Great Britain and Ireland: From Pre-Grouping to the Present Day (1st ed.).