 During the Middle Ages the Parish church of Ystradyfodwg near the bank of the River Rhondda served the parishioners of the Rhondda Fawr , while the families of the Rhondda Fach attended Llanwynno church . The inhabitants of the lower Rhondda , in the vicinity of Porth and Dinas , would need to trek to Llantrisant to hear a service . 
