 Trealaw is a dormitory town of the more famous Tonypandy, its name translates from the Welsh language as 'the Town of Alaw', which derives from Alaw Goch or Alaw Coch (red melody), the bardic name of David (Dafydd) Williams (d. 1863) the father of Judge Gwilym Williams (1839–1906), who founded the village (along with that of Williamstown, a village to the south of Trealaw) during the 'coal-rush' of the 19th century.Judge Williams is also commemorated in Trealaw by Judges Hall (in full, the Judge Gwilym Williams Memorial Hall) and in Ynyscynon Road, named after the Williams' family seat at Ynyscynon, near Aberdare in the Cynon Valley.Judges Hall is a community venue used in its heyday for Variety performances, boxing tournaments and snooker.