Merthyr Tydfil County Borough () is a county borough in the south-east of Wales. In , it had an estimated population of , making it the smallest local authority in Wales by population. It is located in the historic county of Glamorgan and takes its name from the town with the same name. The county borough consists of the northern part of the Taff Valley and the smaller neighbouring Taff Bargoed Valley. It borders the counties of Rhondda Cynon Taf to the west, Caerphilly County Borough to the east, and Powys to the north. The area was awarded county borough status in 1908 until the original county borough was abolished in 1974. In 1996, Merthyr Tydfil became a principal area and one that is styled as a "county borough" in recognition of its historical status.
History
Pre-industrial Merthyr What is now Merthyr Tydfil town centre was originally little more than a village. An ironworks existed in the parish in the Elizabethan period, but it did not survive beyond the early 1640s at the latest. In 1754, it was recorded that the valley was almost entirely populated by shepherds. Farm produce was traded at many markets and fairs, notably the Waun Fair above Dowlais.The Welsh Academy Encyclopedia of Wales. Cardiff: University of Wales Press 2008.
The Industrial Revolution
Influence and growth of iron industry
What is now Merthyr Tydfil County Borough was situated close to reserves of iron ore, coal, limestone and water, making it an ideal site for ironworks. Small-scale iron working and coal mining had been carried out at some places in South Wales since the Tudor period, but in the wake of the Industrial Revolution the demand for iron led to the rapid expansion of Merthyr's iron operations in the northern half of the County Borough. The Dowlais Ironworks was founded by what would become the Dowlais Iron Company in 1759, making it the first major works in the area. It was followed in 1765 by the Cyfarthfa Ironworks. The Plymouth Ironworks were initially in the same ownership as Cyfarthfa, but passed after the death of Anthony Bacon to Richard Hill in 1788. The fourth ironworks was Penydarren built by Francis Homfray and Samuel Homfray after 1784.
The demand for iron was fuelled by the Royal Navy, who needed cannon for their ships, and later by the railways. In 1802, Admiral Lord Nelson visited Merthyr to witness cannon being made.
Several railway companies established routes that linked Merthyr with coastal ports or other parts of Britain. They included the Brecon and Merthyr Railway, Vale of Neath Railway, Taff Vale Railway and Great Western Railway. They often shared routes to enable access to coal mines and ironworks through rugged country, which presented great engineering challenges. In 1804, the world's first railway steam locomotive, "The Iron Horse", developed by the Cornish engineer Richard Trevithick, pulled 10 tons of iron on the newly constructed Merthyr Tramway from Penydarren to Abercynon.Trevithick2004.co.uk A replica of this now resides in the National Waterfront Museum in Swansea. The tramway passed through what is arguably the oldest railway tunnel in the world, part of which can still be seen alongside Pentrebach Road at the lower end of the town.
The 1801 census recorded the population of Merthyr as 7705, the most populous parish in Wales (however, the built-up area of Swansea, covering several parishes, then exceeded 10,000). By 1851 Merthyr had overtaken Swansea to become the largest town in Wales with 46,378 inhabitants. By this time, Irish immigrants made up 10% of the local population, and there were substantial numbers of English, together with some Spaniards and Italians. A Jewish community was established some time after 1841, and by 1851, they were able to establish a small prayer hall. The charming Merthyr Synagogue was consecrated in 1875 and a cemetery at Cefn-Coed was established in the 1860s.
During the first few decades of the 19th century, the ironworks at Dowlais and Cyfarthfa continued to expand and at their peak were the most productive ironworks in the world. 50,000 tons of rails left just one ironworks in 1844, to enable expansion of railways across Russia to Siberia. At its peak, the Dowlais Iron Company operated 18 blast furnaces and employed 7,300 people, and by 1857 had constructed the world's most powerful rolling mill. The companies were mainly owned by two dynasties, the Guest and Crawshay families. One of the famous members of the Guest family was Lady Charlotte Guest who translated the Mabinogion into English from its original Welsh. The families also supported the establishment of schools for their workers.
Thomas Carlyle visited Merthyr town in 1850, writing that it was filled with such "unguided, hard-worked, fierce, and miserable-looking sons of Adam I never saw before. Ah me ! It is like a vision of Hell, and will never leave me, that of these poor creatures broiling, all in sweat and dirt, amid their furnaces, pits, and rolling mills."James Anthony Froude, Thomas Carlyle: A History of his Life in London 1834-1881, Longmans, vol 2, 1855, p. 52.
The Merthyr Rising
The Merthyr Rising of 1831 were precipitated by a combination of the ruthless collection of debts, frequent wage reductions when the value of iron periodically fell, and the imposition of truck shops. Some workers were paid in specially minted coins or credit notes, known as "truck" which could only be exchanged at shops owned by their employers. Many of the workers objected to both the price and quality of the goods sold in these shops.
Some 7,000 to 10,000 workers marched and, for four days, magistrates and ironmasters were under siege in the Castle Hotel, and the protesters effectively controlled Merthyr. Soldiers, called in from Brecon, clashed with the rioters, and several on both sides were killed. Despite the hope that they could negotiate with the owners, the skilled workers lost control of the movement.
Several of the supposed leaders of the riots were arrested. One of them, Richard Lewis, popularly known as Dic Penderyn, was hanged for the crime of stabbing a soldier named Donald Black in the leg. Lewis became known as the first local working-class martyr.
Alexander Cordell's low-brow novel The Fire People is set in this period. A more serious political history of these events, The Merthyr Rising was written by the Merthyr-born Marxist writer Professor Gwyn A. Williams in 1978.
The rising helped create the momentum that led to the Reform Act. The Chartism movement, which did not consider these reforms extensive enough, was subsequently active in Merthyr.
The decline of coal and iron
The steel and coal industries began to decline after World War I, and by the 1930s, they had all closed. By 1932, more than 80% of men in Dowlais were unemployed; Merthyr experienced an out-migration of 27,000 people in the 1920s and 1930s, and a Royal Commission recommended that the town's county borough status should be abolished. The fortunes of Merthyr revived temporarily during World War II, as war-related industry was established in the area. In the post-war years the local economy became increasingly reliant on light manufacturing, often providing employment for women rather than men.
In 1987, the iron foundry, all that remained of the former Dowlais ironworks, finally closed, marking the end of 228 years continuous production on one site.
Post-Second World War Immediately following the Second World War, several large companies set up in Merthyr. In October 1948 the American-owned Hoover Company opened a large washing machine factory and depot in the village of Pentrebach, a few miles south of the town. The factory was purpose-built to manufacture the Hoover Electric Washing Machine, and at one point Hoover was the largest employer in the borough. Later the Sinclair C5 was built the same factory.
Several other companies built factories, including the aviation components company Teddington Aircraft Controls, which opened in 1946. The Teddington factory closed in the early 1970s. The local Merthyr Tydfil Institute for the Blind, founded in 1923, remains the oldest active manufacturer in the town.
The Gurnos housing estate was established by Merthyr Tydfil Council in the early 1950s and expanded over many years. Cyfarthfa, the former home of the ironmaster William Crawshay II, an opulent mock-castle, is now a museum. It houses a number of paintings of the town, a large collection of artefacts from the town's Industrial Revolution period, and a notable collection of Egyptian tomb artefacts, including several sarcophagi.
On 21 October 1966 a colliery tip slid down a mountain at Aberfan, 4 miles (6.4 km) south of Merthyr, covering the village school and causing the Aberfan disaster.
In 1992, while testing a new angina treatment in Merthyr Tydfil, researchers discovered that the new drug had erection-stimulating side effects for some of the healthy volunteers in the trial study. This discovery would go on to form the basis for Viagra.
In 2006 inventor Howard Stapleton, based in Merthyr Tydfil, developed the technology that has given rise to the recent mosquitotone or Teen Buzz phenomenon.
Open cast mining
In 2006, a large open cast coal mine, which will extract 10 million tonnes of coal over 15 years, was authorised just east of Dowlais as part of the Ffos-y-fran Opencast mine.
Industrial legacy Merthyr Tydfil has a long and varied industrial heritage, and was one of the seats of the Industrial Revolution. Since the end of the Second World War, much of this has declined, with the closure of long-established coal mining collieries, and both steel and ironworks. Despite recent improvements, some parts of the County Borough remain economically disadvantaged, and there is a significant proportion of the community who are long-term unemployed.
In Britain today, Merthyr Tydfil: Ranks 13th worst for economic activity Ranks 13th worst for life expectancy: women live on average 79.1 years, and men 75.5. This is lower than the average for England but better than the Scottish and north of England averages Has 30% of the population suffering from a limiting long-term illness.
A Channel 4 programme rated Merthyr Tydfil as the third worst place to live in Britain in 2006 following areas of London.Merthyr Tydfil: Best and Worst Places to Live in the UK 2006 from channel4.com'Third worst place in UK' — but Valleys town disputes claims — icWales However, in the 2007 edition of the same programme, Merthyr had 'improved' to fifth worst place to live.Channel4.com
Governance Merthyr Tydfil County Borough Council is the governing body for the area. It consists of 30 councillors representing 11 wards.
The current Member of Parliament for the Merthyr Tydfil and Aberdare constituency is Gerald Jones MP. In the Senedd, Merthyr Tydfil County Borough became part of the new Pontypridd Cynon Merthyr Senedd seat in 2026.
The county borough is divided into twelve communities. Only one of the communities has a community council, being Bedlinog (also covering Trelewis), in the Taff Bargoed Valley to the east of the borough. The Bedlinog community covers the area that was transferred to the borough of Merthyr Tydfil in 1974 from Gelligaer Urban District under the Local Government Act 1972.
Administrative history Merthyr Tydfil was an ancient parish within the county of Glamorgan. As well as the village of Merthyr Tydfil itself, the parish covered much of the upper Taff Valley, including settlements stretching from Dowlais in the north to Aberfan and Treharris in the south. It was governed by its parish vestry, in the same way as most rural parishes. As the area rapidly developed during the industrial revolution, it was decided that a more formal type of local government was required, particularly to oversee sanitation and public health in the parish. The parish was made a Local Board District on 19 June 1850, governed by an elected local board of health.