The Great Western Railway, also known as the GWR, was founded by Royal Assent on 31 August 1835. The idea of a railway from Bristol to London had first been mooted in 1824, and finally in 1833 a committee of four prominent Bristol businessmen, namely George Jones, John Harford, Thomas Richard Guppy and William Tothill, had joined together and provided impetus and capital for the project. It took two years to survey the line and push the necessary legislation through Parliament. The first train ran from Bristol to Bath on 31 August 1940, full services started in 1841 and in 1842 Swindon Locomotive Works started operation. The London terminus of the GWR was at Paddington station. At its inception, the GWR had a board of 24 directors which was divided into two committees based in London and Bristol. The first chairman, who sat on the London committee, was Benjamin Shaw and the first deputy chairman was Robert Bright, a member of the Bristol committee. Sir Daniel Gooch was the first Locomotive Superintendent, a post that came later to be known as the Chief Mechanical Engineer. The GWR did not have the post of General Manager until 1863, when Charles Grierson was appointed. The first Secretary was Charles Saunders. Charles Russell became chairman in 1839. The GWR’s first Engineer (a post that would later be called the Chief Civil Engineer) was the renowned Isambard Kingdom Brunel, and he held the post from March 1835 to September 1859. The GWR was overseen by a Board of Directors. At the turn of the century there were three departments under the General Manager. These were the General Department, New Works and Government Enquiries and Staff and Expenses. On the operational side of the GWR, the various different departments such as the Locomotive, Carriage and Superintendent, the Superintendent of the Line, the Goods Department and the Traffic Manager all used a similar administrative structure. These departments were headed by one manager and beneath this post responsibility was distributed into divisions based on geographical areas, which varied by department. The docks which were owned by the GWR were administrated separately from the railways under the control of the Chief Docks Manager. There were also facilitative administrative departments, as well as Hotels and Catering, Surveyor, Estate Agent, Stores departments and a Road Motor Engineer’s Department which operated the GWR’s road haulage service. Brunel insisted on using a broad gauge track, which caused problems both in the civil engineering projects to build the railway and also during operation. A Gauge Commission had been appointed in 1846 and brought about the Gauge Act of 16 August 1846 which noted the systemic advantages of narrow gauge but did not compel the GWR to convert the full length of their track. From 1846 a standard gauge third rail was added to board gauge lines. From around 1868, led by then Chairman Sir Daniel Gooch, the GWR began to convert the entire system to standard gauge, and this was completed on 23 May 1892. The main line of the Great Western Railway ran over the 118¼ miles between Bristol Temple Meads and Paddington station in London. The construction of the main line required several major engineering works. The chief among these was the two-mile long Box Tunnel between Bath and Chippenham. This challenging engineering work took around five years to complete, opening on 30 June 1841. Brunel also constructed viaducts and bridges, including the Maidenhead Bridge, opened on 1 July 1839 and the Royal Albert Bridge at Saltash which linked Devon and Cornwall across the River Tamar and which opened on 11 April 1859. The GWR had a road haulage operation, which connected with its rail freight services. The GWR also owned and operated a number of docks and harbours, and after the Grouping in 1923 the GWR became the world’s largest dock-owning company. It wholly owned 16 docks, including Plymouth, Swansea and Cardiff, and jointly owned five other docks. The South Wales ports mainly handled minerals and food, whilst passenger ships used Plymouth and Fishguard. The GWR’s docks and harbours allowed goods and passengers to transfer between rail and sea with ease. The GWR also owned its own hotels, which numbered eight by 1923. The showpiece hotel was the Great Western Royal Hotel which was connected to Paddington station. The Railways Act 1921 came into effect on 1 January 1923 and the multitude of smaller railway companies were consolidated in the Big Four. The GWR absorbed seven larger constituent companies as well as 26 smaller railways covering most of Wales, the Welsh Marches, Somerset, South Devon and Cornwall. It was third largest Big Four railway, with around 3,800 miles of track. The Great Western Railway, along with all the other Big Four railway companies was nationalised and taken over by the Railway Executive, part of the British Transport Commission from 1 January 1948. The Western Region of British Railways took over responsibilty for GWR's sphere of operations.

The East Indian Railway Company subsequently known as the East Indian Railway (EIR) was a pioneering company that introduced rail to Bengal and beyond in eastern India. The company was based in Calcutta. Founded in 1845.

The Great North of Scotland Railway (GNSR) was promoted to build a line from Aberdeen to Inverness and incorporated in 1846. It operated in Aberdeenshire. The first section built was from Kittybrewster (one and a half miles outside Aberdeen) to Huntly which was opened in 1854. The line was extended into Aberdeen to a terminus at Waterloo Quay in 1855 and from Huntly to Keith in 1856. There it made an end-on junction with the Inverness and Aberdeen Junction Railway (soon to become the Highland Railway). In 1867 it opened a joint station in Aberdeen with the Caledonian Railway thereby removing the difficult transfer of goods and passengers between the two companies' separate terminuses. The GNSR expanded by absorbing smaller companies and building branch lines, eventually extending to just over 333 route miles. It extended as far north as Lossiemouth with two routes to Elgin and branch lines to Peterhead, Fraserburgh, Macduff and Ballater. Ballater was the station that served Balmoral Castle. Although the 'main line' from Aberdeen to Keith was doubled between 1861 and 1900, much of the system was single track. The GNSR was an early user of automatic single line token exchange equipment. Most passenger journeys were local although GNSR did try to encourage tourism by building a hotel at Cruden Bay. Its goods traffic included fish, fat cattle and the products of the distilleries in the Spey Valley. Its locomotive works were at Kittybrewster until the end of the nineteenth century when they were moved to Inverurie. William Pickersgill was locomotive superintendent from 1894 to 1914. The GNSR became part of the London & North Eastern Railway under Grouping in 1923. The only part of the GNSR now open is the 'main line' from Aberdeen to Keith.

Railway built to link Edinburgh and Glasgow which received its Royal Assent in 1838 and opened in 1842. The line was absorbed into the North British Railway on 1 August 1865.

Formed on 6th October, 1846, by the combination of the Staffordshire Junction Railway & The Trent Valley, Midlands & Grand Junction Railways. Despite opening up 19 miles of track early in their history, the line was leased to the London & North Western Railway in February, 1861. On the 15th June, 1897, the South Staffordshire Railway Company was dissolved and the London & North Western Railway took over complete ownership.

Government agency created in 1887 with the task of managing all state-owned railway lines in Sweden.

Colliery company in Staffordshire, active 1821-1946.

Spainish railway, active 1856

Irish railway linking Belfast with County Down. Incorporated in 1846, with the first section opening in 1848. It was absorbed into the Ulster Transport Authority in 1948.

Irish railway company formed in 1876 by the merger of the Irish North Western Railway (INW), Northern Railway of Ireland, and Ulster Railway. In 1958, under the Great Northern Railway Act, which became operative on 1st October 1958, the Great Northern Railway rail and road services within Eire were amalgamated with Coras Iompair Eireann.

In 1851 the Regent of Egypt and Sudan, Abbas I, contracted Robert Stephenson to build Egypt's first standard gauge railway. Construction began on the line in 1851 and in 1854 a section was opened from Alexandria to the village of Kafr El-Eiss. In 1856 the entire single track line was opened with 12 stations including the main stations of Cairo (constructed in 1855) and Alexandria (constructed in 1854). In 1919, the railways became entrusted to the Ministry of Communications and in 1953, Egypt became a republic and Egyptian State Railways changed to become Egyptian Republic Railways.

The Belgian State Railways was the original state-owned railway of Belgium, established in 1834. The first line, between Brussels and Mechelen opened on 1835 and was the first steam powered public railway in continental Europe. Its assets and operations were transferred to the newly created National Railway Company of Belgium in September 1926.

Italian railway company which had concession for the construction and operation of the railway network in the Kingdom of Lombardy–Venetia and central Italy between 1856 and 1859.

Formed after Manchester, Bury & Rossendale Railway changed their name in July 1845; a year later ELR absorbed Blackburn & Preston, the Blackburn, Burnley, Accrington & Colne Extension and Liverpool, Ormskirk & Preston Railway; there was an extension in 1852 to Bacup for passengers; Lancashire & Yorkshire Railway absorbed East Lancashire Railway in May 1859.

Scottish railway company, established in 1836. It became a constituent of the London, Midland and Scottish Railway in 1923.

Irish railway company. It received royal assent to construct the railway line between Dublin and Drogheda on 13 August 1836. The railway officially opened on 25 May 1844. The company merged with the Dublin and Belfast Junction Railway in 1875 to form the Northern Railway of Ireland.

Formed in 1852, incorporated by Act of Parliament, 1853. Main lines ran west from Madras to Bangalore via Jalarpet, south west from Jalarpet to the Malabar Coast at Calicut and north west to Raichur. In 1901, the company took over the portion of the East Coast State Railway between Vizagapatam and Madras, and in 1903 the Nilgiri Railway from Mettupalaiyam to Coonoor. The Madras Railway was purchased by Government in 1907. The northern portion was given over for working to the Southern Mahratta Railway, which became known as the Madras and Southern Mahratta Railway, the southern portion became part of the South Indian Railway.

The Midland Railway was formed in 1844 from the merger of the Midland Counties Railway, the North Midland Railway and Birmingham and Derby Junction Railway wit its headquarters in Derby. It expanded its operational territory by acquisition (e.g. railways in the Erewash valley, to Sheffield, serving the Leicestershire coalfields and the route from Birmingham to Bristol), and by construction of new railways and extensions to existing lines, including lines to Peterborough and Lincoln, towards Manchester and, most notably the Settle to Carlisle route. It expanded into the South Wales coalfields, and acquired railways not connected to its main routes: the London, Tilbury and Southend Railway and, in Ireland, the Belfast and Northern Counties Railways. Much of this activity was driven by competition with its geographical rivals, the London and North Western Railway to the west and the Great Northern Railway to the east. Where its interests were better served by co-operation, it tried to reach agreements with those same companies to share routes and traffic receipts. The most famous of these is the Euston Square Confederation, an agreement between the Midland Railway, the London and North Western Railway and the Manchester, Sheffield and Lincolnshire Railway. Other such arrangements were the Cheshire Lines Committee and the right to run over the Great Northern Railway into King’s Cross station. The arrangements for through running and sharing of London termini with its competitors proved unsatisfactory. As a consequence the Midland Railway eventually built its own connection to London. The line ran from Bedford on the Midland’s existing Leicester to Hitchin line, to a terminus at St Pancras. It was opened in 1868. The Midland Railway was a partner in several joint railways e.g. the Somerset and Dorset Joint Railway (with the London and South Western Railway), and the Midland and Great Northern Joint Railway (the Great Northern Railway). The Midland Railway came under the control of the Railway Executive during the First World War and ended its independent existence in 1923 under Grouping when it was merged with, amongst other railway companies, its great rival the London and North Western Railway to form the London, Midland and Scottish Railway Company.

The Brymbo Iron Co was formed in 1842 to manage the Brymbo Iron works, which had been founded in 1793. The company was incorporated as the Brymbo Steel Co in 1884.

Colliery management company in Wrexham, active 1896 to nationalisation in 1947.