South Wales valleys
Coordinates: 51°46′23″N 3°20′42″W / 51.773°N 3.345°W
The South Wales Valleys (Welsh: Cymoedd De Cymru) are a number of industrialised valleys in South Wales. Commonly referred to locally as The Valleys (Welsh: Y Cymoedd), they stretch from eastern Carmarthenshire in the west to western Monmouthshire in the east and from the Heads of the Valleys in the north to the edge of the lower-lying, pastoral country of the Vale of Glamorgan and the coastal plain around Swansea Bay, Bridgend, the capital Cardiff, and Newport. Many of the valleys run roughly parallel to each other. The Rhondda Valleys and the Cynon Valley are located roughly in the centre.
Until the mid-nineteenth century, the South Wales valleys were lightly inhabited. The industrialisation of the Valleys occurred in two phases. First, in the second half of the 18th century, the iron industry was established on the northern edge of the Valleys, mainly by English entrepreneurs. This made South Wales the most important part of British ironmaking until the middle of the 19th century. Second, from 1850 to the outbreak of the First World War, the South Wales Coalfield was developed to supply steam coal and anthracite.
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