ABERYSTWYTH (ab-ur-iist'with), watering-place and uni versity town on the shores of Cardigan bay, Wales, at the mouth of the artificially united Rheidol and Ystwyth rivers. Population (1931) 9,474 but in the summer months these figures are aug mented by the presence of visitors. There appears to be a long tradition of settlement in the neighbourhood, for on a prominent hill (Pendinas) overlooking the south of the town is one of the largest hill-top earthworks in central Wales. With the clearing of the lowland, Pendinas was superseded by Llanbadarn Fawr, a village situated on a dry bend above the flood plain of the Rheidol about II- m. E. of the town. The existence of three Norman motte and bailey castles in the neighbourhood suggests loose military tenure in early Plantagenet times. The most interesting of these sites is Castell Aberystwyth situated above the bend of the Ystwyth about 12 m. S. of the town. It gave its name to the Edwardian stone castle erected near the fishing village that grew up at the river mouths. The history of the castle was a trouble some one, as was to be expected from its position in the heart of Wales, but future developments centred in the little community that gathered beneath it, and not in Llanbadarn Fawr. Traces of the mediaeval town wall are still to be seen.
Aberystwyth shared in the mining (lead), agricultural and sea trade movements of the early 59th century and seems to have become at this time the social centre for the surrounding area. It has since extended northwards and eastwards over the newly drained marshy ground that surrounded the mediaeval settlement, and has gained favour as a summer health resort, especially since the development of the railway. The latter, however, killed the coastal trade and much of the seafaring habit (see CARDIGAN SHIRE). In spite of this loss of old activities, Aberystwyth did not become a mere watering-place. As a link between the northern and southern parts of Welsh Wales, it became the site of the first University college of Wales, opened in 1872 and incorporated by charter in 1889, and of the National Library of Wales, opened in 1911. In 1906 the Welsh Calvinistic Methodist Theological college was moved here from Trevecca. Aberystwyth was a con tributory parliamentary borough until 1885, when its representa tion was merged in that of the county.