Under the Railways Act 1921 the majority of the railway companies in Great Britain (along with a few in Northern Ireland) were grouped into four main companies, often termed the Big Four. The grouping took effect from 1 January 1923.
The Big Four
The Big Four and their constituent companies, showing route mileage, were:
Companies not covered by the grouping
Over fifty railway companies were not covered by the grouping. Those in the following list were those organised on an independent basis, usually providing locomotives and rolling stock also. They are included under classification headings.
Joint railways
Joint lines in this respect were wholly owned by two or more other companies. If not all of the owning companies went into the same group then the joint company could not be grouped. Joint lines did not always operate any services: they owned the track, stations etc. and the services were operated by one or more of the parent companies:
- These are those in which the group companies only are concerned:
- Cheshire Lines Committee: (GNR, Midland and GCR); now operated under direction of a board of directors appointed by LNER (two-thirds) and LMS (one-third). Length 142 miles (229 km). Rolling stock owned by CLC; locomotive power by LNER.
- Great Western and Great Central Joint Railway: GWR and GCR; subsequent to the grouping the parent companies were the GWR and the LNER, but the title was not altered.
- Manchester, South Junction and Altrincham Railway: LNWR and GCR; subsequent to the grouping the parent companies were the LMS and the LNER.
- Midland and Great Northern Joint Railway: (Midland and GNR; subsequent to the grouping the parent companies were the LMS and the LNER). Length 183 miles (295 km). This was the largest joint system in the UK, and many of the services were operated by the joint company itself. In addition, it received substantial traffic from the GNR and MR/LMS, but rather less post-grouping from the LNER (which also owned the competing ex-GER system in East Anglia).
- Somerset and Dorset Joint Railway: (Midland and LSWR). Length 105 miles (169 km).
- Joint lines where one or more partners were ungrouped:
- Aylesbury Station: joint between the GW & GC Joint and the Metropolitan and Great Central Joint Committee
- East London Railway: prior to grouping, this railway was owned one-sixth each by the Great Eastern Railway, London, Brighton and South Coast Railway, Metropolitan Railway, District Railway; and one-third by the South Eastern and Chatham Railway (as successors to the London, Chatham and Dover Railway and South Eastern Railway, who had owned one-sixth each). After grouping, it was owned half by the Southern, and one-sixth each by the LNER, Metropolitan and District. Length 5 miles (8 km). Managed and operated by Met; goods traffic by LNER.
- Metropolitan and Great Central Joint Committee: prior to grouping, owned by the Metropolitan Railway and GCR; post-Grouping, Metropolitan and LNER.
Railways not included in group companies
Electric or electric and steam lines
Light and similar railways (standard gauge)
Light and similar railways (narrow gauge)
Railways outside the jurisdiction of the Railways Act 1921
The Railways Act 1921 only extended to Great Britain. Railways in Ireland and the Crown Dependencies were not affected unless owned by a railway company in Great Britain. The railways included in this section were standard gauge, unless otherwise noted:
- Alderney Railway
- Belfast and County Down Railway; 5 ft 3 in (1,600 mm)
- Cork, Bandon and South Coast Railway; 5 ft 3 in (1,600 mm); 94 miles (151 km)
- Dublin and South Eastern Railway; 5 ft 3 in (1,600 mm); 161 miles (259 km)
- Great Northern Railway (Ireland); 5 ft 3 in (1,600 mm);
- Great Southern and Western Railway; 5 ft 3 in (1,600 mm); 1,100 miles (1,770 km)
- Guernsey Railway; 3 miles (5 km)
- Isle of Man Railway; 3 ft (914 mm); 46+1⁄4 miles (74 km)
- Jersey Eastern Railway; 6+1⁄4 miles (10 km)
- Jersey Railway and Tramways; 3 ft 6 in (1,067 mm); 7+1⁄2 miles (12 km)
- Londonderry and Lough Swilly Railway; 3 ft (914 mm)
- Sligo, Leitrim and Northern Counties Railway; 5 ft 3 in (1,600 mm)
- Manx Electric Railway; 3 ft (914 mm); 18 miles (29 km); and 3 ft 6 in (1,067 mm); 5 miles (8 km)
- Midland Great Western Railway; 5 ft 3 in (1,600 mm); 538 miles (866 km)
Miscellaneous railways
The railways included in this section were standard gauge, unless otherwise noted:
See also