industrial town, Rhondda Cynon Taff (Rhondda) county borough, historic county of Glamorgan (Morgannwg), Wales, at the confluence of the Rivers Rhondda and Taff. Pontypridd is a shopping centre for the Rhondda and middle Taff valleys. Its historic coal-mining and chain-making industries have declined dramatically, but a variety of light engineering and other manufactures have developed, especially on the Treforest Industrial Estate. A single-span, 140-foot (43-metre) bridge over the Taff, no longer in use, was constructed in 1736 by William Edwards, a local stonemason. Pop. (2001) 29,781.