Southern Wales

South Wales (Welsh: De Cymru) is the region of Wales bordered by England and the Bristol Channel to the east and south, and Mid Wales and West Wales to the north and west. The most densely populated region in the southwest of the United Kingdom, it is home to around 2.2 million people. The region contains almost three-quarters of the population of Wales, including the capital city of Cardiff (population approximately 350,000), as well as Swansea and Newport, with populations approximately 240,000 and 150,000 respectively. The Brecon Beacons national park covers about a third of South Wales, containing Pen y Fan, the highest mountain south of Snowdonia.

The region is loosely defined, but it is generally considered to include the historic counties of Glamorgan and Monmouthshire, sometimes extending westwards to include Carmarthenshire and Pembrokeshire. In the western extent, from Swansea westwards, local people would probably recognise that they lived in both south Wales and west Wales — there is considerable overlap in these somewhat artificial boundaries. Areas to the north of the Brecon Beacons and Black Mountains are generally considered part of Mid Wales.

The expression 'south Wales' is not officially defined, and its meaning has changed over time.

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