River Rhondda - Course

Course

The Rhondda Fawr has its source near Llyn Fawr in a spring called Ffynnon y Gwalciau. The main head stream, Nant Carn Moesen, runs down a plateau slope for about two miles before descending sharply through a mountain gorge to the foot of Pen Pych. The river runs through Blaenrhondda where it is joined by the Nant y Gwair via a classic example of a hanging valley, and runs down the Rhondda Valley, (Welsh: Cwm Rhondda). The river then passes through a string of mining towns and villages including Treherbert, Treorchy, Pentre, Ton Pentre, Ystrad Rhondda, Llwynypia, Tonypandy, Dinas, Porth and Trehafod before finally reaching its confluence with the River Taff at Pontypridd.

The Rhondda Fach rises very close to the Rhondda Fawr on the hills above Blaenrhondda in a marshy area between Mynydd Beili Glas and Mynydd Bwllfa. The fledgling river is first contained in the Lluestwen reservoir before flowing down into Maerdy and then on through Ferndale, Tylorstown, and Ynyshir before joing its sister tributary at Porth.