List of constituents of the Great Western Railway
The Great Western Railway was incorporated by Act of Parliament in 1835 and nationalised on 1 January 1948. During this time it amalgamated with, or purchased outright, many other railway companies. These are listed here in two groups. The early amalgamations often involved railway companies that were already being financially supported by the GWR. The Railways Act 1921 brought many new companies into the fold including many successful Welsh lines.
Key:
Early amalgamations and purchases
- Cheltenham and Great Western Union Railway ♠ ‡
- Oxford and Rugby Railway ♠ ‡
- Berks and Hants Railway ♠ ‡
- Monmouth and Hereford Railway
- Wilts, Somerset and Weymouth Railway ♠ ‡
- Shrewsbury and Birmingham Railway
- Shrewsbury and Chester Railway
- Birkenhead Railway
- * Chester and Birkenhead Railway
- * Birkenhead, Lancashire and Cheshire Junction Railway
- South Wales Railway ♠ ‡
- West Midland Railway
- * Newport, Abergavenny and Hereford Railway
- * Oxford, Worcester and Wolverhampton Railway
- * Worcester and Hereford Railway
- * Severn Valley Railway
- Vale of Neath Railway ‡
- * Aberdare Valley Railway
- Wycombe Railway ♠
- Bristol and South Wales Union Railway ♠ ‡
- Tenbury and Bewdley Railway
- Stourbridge Railway
- Great Western and Brentford Railway ♠
- Wallingford and Watlington Railway
- Wrexham and Minera Railway
- Llanelly Railway
- Llynvi and Ogmore Railway
- * Llynvi Valley Railway
- * Ogmore Valley Railway
- Gloucester and Dean Forest Railway ♠
- East Somerset Railway ♠
- Bristol and Exeter Railway ‡
- South Devon Railway ‡
- * Dartmouth and Torbay Railway
- * Launceston and South Devon Railway
- * Moretonhampstead and South Devon Railway
- * South Devon and Tavistock Railway
- West Cornwall Railway ‡
- * Hayle Railway
- Wellington and Drayton Railway ♠
- Monmouthshire Railway ♠
- Culm Valley Light Railway ♠
- Malmesbury Railway ♠
- Carmarthen and Cardigan Railway
- Berks and Hants Extension Railway ♠
- Torbay and Brixham Railway ♥
- Festiniog and Blaenau Railway
- Stratford-upon-Avon Railway ♠
- Watlington and Princes Risborough Railway
- Whitland and Cardigan Railway
- Faringdon Railway
- Worcester, Bromyard and Leominster Railway
- Cornwall Railway ‡
- Calne Railway ♠
- Newent Railway
- Ross and Ledbury Railway
- Wellington and Severn Junction Railway
- Cornwall Minerals Railway ♠
- * Lostwithiel and Fowey Railway
- * Newquay and Cornwall Junction Railway
- * Newquay Railway
- * Par Tramway
- Pembroke and Tenby Railway
- Corwen and Bala Railway
- Llangollen and Corwen Railway
- Marlborough Railway
- Milford Railway
- Vale of Llangollen Railway
- Wenlock Railway
- Banbury and Cheltenham Direct Railway
- Buckfastleigh, Totnes and South Devon Railway
- Kington and Eardisley Railway
- Nantwich and Market Drayton Railway ♠
- Minehead Railway ♠
- North Pembrokeshire and Fishguard Railway
- * Maenclochog Railway
- * North Pembrokeshire and Fishguard Railway
- Helston Railway ♠
- Leominster and Kington Railway
- Staines and West Drayton Railway ♠
- Golden Valley Railway ♠
- Bridport Railway ♠
- Devon and Somerset Railway ♠
- Ely Valley Railway
- Wye Valley Railway
- Lambourn Valley Railway
- Manchester and Milford Railway
- Bala and Festiniog Railway
1921 Railways Act
- Alexandra Docks and Railway miles
- Barry Railway 68 miles
- * Vale of Glamorgan Railway miles ♠
- Cambrian Railways miles
- * Aberystwith and Welsh Coast Railway
- * Llanidloes and Newtown Railway
- * Mawddwy Light Railway ♠
- * Mid-Wales Railway
- * Newtown and Machynlleth Railway
- * Oswestry, Ellesmere and Whitchurch Railway
- * Oswestry and Newtown Railway
- * Tanat Valley Light Railway
- * Vale of Rheidol Railway
- * Van Railway ♠
- * Welshpool and Llanfair Light Railway ♠
- * Wrexham and Ellesmere Railway ♠
- Cardiff Railway miles
- Cleobury, Mortimer and Ditton Priors Railway 12 miles
- Port Talbot Railway 35 miles
- * South Wales Mineral Railway 13 miles ♠
- Princetown Railway miles
- Rhondda and Swansea Bay Railway 29 miles
- Rhymney Railway 51 miles
- Taff Vale Railway miles
- * Penarth Extension Railway miles ♠
- * Penarth Harbour, Dock and Railway miles ♠
- West Somerset Railway miles ♠
- Brecon and Merthyr Railway miles
- Burry Port and Gwendraeth Valley Railway 21 miles
- Neath and Brecon Railway
- Gwendraeth Valley Railways 3 miles ♠
- Llanelly and Mynydd Mawr Railway 13 miles
- Didcot, Newbury and Southampton Railway miles ♠
- Midland and South Western Junction Railway miles
- Swansea Harbour Trust
- Powlesland and Mason
- East Gloucestershire Railway miles ♠
- Exeter Railway miles ♠
- Forest of Dean Central Railway 5 miles ♠
- Lampeter, Aberayron and New Quay Light Railway 12 miles ♠
- Liskeard and Looe Railway 9 miles ♠
- Ross and Monmouth Railway miles ♠
- Teign Valley Railway miles ♠