Duffryn House was the home of Lord Aberdare. It was a substantial mock-Elizabethan, 2-storey and attics building with ornate tall chimneys, gable timber finials, fretted eaves boards, a pyramid roofed tower and half-timbering. In 1926 the house was purchased by the Glamorgan Education Authority and became the County Grammar School, later part of Mountain Ash Upper Comprehensive School. The house was used for lessons up until 1983, when it was found to be unsafe and eventually demolished.

George Bower reported in his book of 1866, that he had built a gasworks for Howell Gwyn Esq. MP and resident of Duffryn House, Neath c1850’s. An article in the Cambrian from the 7th September 1906, referred to a John Cook a Blacksmith who worked in the private gasworks at Duffryn House. The gas would have been used to light the house with gas. The gasometer was featured on the OS maps between 1877 and 1936.

References: Rhondda Cynon Taf Library Service (2006), early postcards.
RCAHMW, 2010.