ABERDARE, industrial town of north Glamorganshire, Wales, situated, as its name implies, at the confluence of the Dar and Cynon (the latter being a tributary of the Taff). Population (1931) 48,751. The neighbouring moorlands show evidences of occupation in pre-Roman times, and a site about 4m. to the north west of the town is reputed to be the scene of a Norman victory over the native forces under Rhys ap Tewdwr in the iith century. Aberdare remained but a small nucleus among the scattered farms of the moorlands until the beginning of the 19th century when the place grew rapidly owing to the abundance of its coal and iron ore, and the population of the whole parish (which was only 1,486 in 1801) increased tenfold during the first half of the century. Ironworks were established at Llwydcoed and Abernant in 1799 and 1800 respectively, followed by others at Gadlys and Abera man in 1827 and 1847. The building of the Glamorgan canal in 1811 connected these ironworks with the coast, but the rapid development of the railways superseded the canals and at the same time gave an impetus to the iron trade between 1820 and 1870 and a consequent rapid growth of the town. These ironworks have not been worked since 1875, and the only supplementary industry remaining in the town is a small tinplate works at Gadlys (established in 1868). Previous to 1836, most of the coal worked in the parish was consumed locally, chiefly in the ironworks, but in that year the working of steam coal for export was begun, pits were sunk in rapid succession, and the coal trade, which at least since 1875 has been the chief support of the town, soon reached huge dimensions. There are also several brickworks and breweries.
Until 1918 Aberdare was included for parliamentary representa tion with the borough of Merthyr Tydfil, but since that date it returns a member to parliament jointly with the urban district of Mountain Ash.