Merthyr Tydfil

Merthyr Tydfil (Welsh: Merthyr Tudful) is the main town in Merthyr Tydfil County Borough, Wales, administered by Merthyr Tydfil County Borough Council. It is about 23 miles (37 km) north of Cardiff. Often called just Merthyr, it is said to be named after Tydfil, daughter of King Brychan of Brycheiniog, who according to legend was slain at Merthyr by pagans about 480 CE. Merthyr generally means "martyr" in modern Welsh, but here closer to the Latin martyrium: a place of worship built over a martyr's relics. Similar place names in south Wales are Merthyr Cynog, Merthyr Dyfan and Merthyr Mawr.

Noted for its industrial past, Merthyr was known as the 'Iron Capital of the World' in the early 19th century, due to the scale of its iron production. The world's first steam-powered railway journey happened in Merthyr in 1804, travelling 9 mi (14 km) from the ironworks at Penydarren to the Glamorganshire Canal on the Merthyr Tramroad. The 1851 census found Wales to be the world's first industrialised nation, as more people were employed in industry than agriculture, with Merthyr the biggest town in Wales at that time. The city of Donetsk in Ukraine (then in the Russian Empire), originally 'Hughesovka', was founded by John Hughes of Merthyr in 1870, when he took iron working to the area. Iron production declined in Merthyr from 1860 on, though Merthyr's population continued to rise due to the emergence of coal mining in the area, peaking with around 81,000 people in 1911.

The area is currently known for its industrial heritage and adventure tourism. Merthyr and the surrounding areas boast the Grade-I listed Cyfarthfa Castle, the world’s fastest seated zip line, the UK's largest mountain bike park, the largest indoor climbing wall in Wales, national cycle routes and plans for the UK's longest indoor ski slope.

Peoples migrating north from Europe had lived in the area for many thousands of years. The archaeological record starts from about 1000 BCE with the Celts. From their language, the Welsh language developed. Hillforts were built during the Iron Age and the tribe that inhabited them in the south of Wales was called the Silures, according to Tacitus, the Roman historian of the Roman invaders.

The Romans arrived in Wales by about 47–53 CE and established a network of forts, with roads to link them. They had to fight hard to consolidate their conquests, and in 74 CE they built an auxiliary fortress at Penydarren, overlooking the River Taff. It covered an area of about three hectares, and formed part of the network of roads and fortifications; remains were found underneath the Merthyr Town F.C. football ground. A road ran north–south through the area, linking the southern coast with Mid Wales and Watling Street via Brecon. Parts of this and other roads, including Sarn Helen, can be traced and walked.

The Silures resisted this invasion fiercely from their mountain strongholds, but the Roman army eventually prevailed. In time, relative peace was established, and the Penydarren fortress was abandoned by about 120 CE. This was bad for the local economy, which had come to rely upon supplying the fortress with beef and grain, and imported items such as oysters from the coast. The Romans had intermarried with local women and many auxiliary veterans had settled on farms locally.

With the decline of the Roman Empire, Roman legions were withdrawn about 380 CE. By 402, the Roman army in Britain consisted mostly of Germanic troops and local recruits; the cream of the army had been withdrawn to the continent of Europe. Sometime in that period, Irish Dalriadans (Scots) and Picts attacked and breached Hadrian's Wall. During the 4th and 5th centuries the coasts of Cambria (Wales) had been subject to the raids of Irish pirates, in much the same way as the south and east coasts of Britain had been raided by Saxon pirates from across the North Sea. Around the middle of the 5th century, Irish settlements had been established around Swansea, the Gower Peninsula, Carmarthenshire, and in Pembrokeshire and eventually petty kingdoms were established as far inland as Brecon.

The Latin language and some Roman customs and culture became established before the withdrawal of the Roman army. The Christian religion was introduced throughout much of Wales by the Romans, but locally it may have been introduced later by monks from Ireland and France, who made their way into the region following rivers and valleys.