South Glamorgan

South Glamorgan, former county, southern Wales, bounded on the north and west by Mid Glamorgan, and on the east and south by the Bristol Channel. South Glamorgan was formed under the local government reforms of 1974 from the merger of a small part of the former county of Monmouthshire and part of Glamorganshire, which was divided into three new counties: South, West, and Mid Glamorgan. South Glamorgan ceased to exist on April 1, 1996, being divided to form the major parts of the new county of Cardiff and the new county borough of Vale of Glamorgan. This was a result of administrative changes implemented under the Local Government Act 1994, which provided for the replacement of the two-tier system of county and district councils introduced in 1974 by a single-tier system of unitary authorities. South Glamorgan was the smallest of the post-1974 Welsh counties, with a land area of 416 sq km (161 sq mi). The city of Cardiff was the administrative centre.

South Glamorgan had two distinct areas: the urbanized coastal plain of estuarine flats and the rich fertile Vale of Glamorgan, a plateau area varying in height from 60 to 120 m (200 to 400 ft). The principal rivers of South Glamorgan were the Ely, the Taff, and the Rhymney.

South Glamorgan was the most densely populated of the Welsh counties. Only about 6.5 per cent of the population spoke Welsh. The city and port of Cardiff was made the official capital of Wales in 1955. The only other sizeable urban areas were the seaside resorts of Barry (1991, 49,887) and Penarth (1991, 23,434). As well as South Glamorgan county council based in Cardiff, South Glamorgan had two district councils: Cardiff and the Vale of Glamorgan.

With the decline of the coal industry after the 1920s, Cardiff docks lost most of their former importance. In the early 1990s the docklands were redeveloped into a commercial and leisure area, with offices, restaurants, theatres, parks, and sports facilities. Diversification into newer industries was helped by the proximity of Rhoose Airport, and by the city's road and motorway links to the south-east and Midlands of England. Away from Cardiff, agriculture and tourism were the most important contributors to the county's economy.