Taff's Well thermal Spring - The average temperature at Taff's Well spring, 21.6 °C is over 10 °C warmer than the average groundwater temperature of 11.3 °C in Wales.
The well enclosure building is open during the Summer months from 10am to 4pm. for viewing only.
There is an audio playback device inside the building, speaking in Welsh & English giving the history of the Well going back to Roman times.
There is no bathing allowed, & as can be seen in some of the gallery photos there appears to be an orange algae floating on the surface.
From a PDF file titled: Waters from the deep - Natural Environment Research Council, Website:
"A short train journey from Cardiff, hidden away in a small dilapidated Victorian stone building, is perhaps one of Wales’ most unusual natural wonders. Many people will have heard of its name, ‘Taff’s Well’, which is also, and by no coincidence, the name given to the village in which it can be found. Taff’s Well is the only thermal – or warm water spring in Wales, and is one of only a handful to occur in the UK, the Roman Bath hot springs being the most famous example.
A 5,000 year journey So what makes these waters unique? Primarily it is the temperature: bubbling to the surface, the water maintains a constant 21 oC, twice that of a ‘normal’ spring that you may encounter on a walk in the Welsh countryside, but still less than the 45oC you could expect at Bath. Carbon-14 isotope dating suggests that the rain which feeds the well fell at least 5,000 years ago, at a time when the Welsh population lived, at best, in huts, and brown bears roamed the forests. Rainwater falling somewhere along the heads of the valleys moves slowly underground, via cracks and fissures in the bedrock. The waters then flow to a depth" Text Source: Waters from the Deep NERC.
"Taff's Well thermal spring is located in Taff's Well (Welsh: Ffynnon Taf) north of Cardiff, South Wales, UK (National Grid Reference ST 11925 83639) and an elevation of about 30 m. It is the only thermal spring in Wales. The spring emerges on the eastern bank of the River Taff and has been contained within a brick well structure and building. Access is via Taff's Well park, a public park, owned and maintained by "Rhondda Cynnon Taff Council".
The spring is enclosed inside a well and stone building constructed in the 19th century. The well built to contain the spring waters is brick lined and approximately 4 m deep. The building has an internal dimension of 5.3 × 3.9 m, and water fills this area.[1] A brick built spiral staircase is incorporated in the inside of the well. There is one visible overflow pipe which emerges several meters to the west of the spring, on the bank of the River Taff.
A recent conceptual model considers that the water has journeyed from the limestone outcrops on the north crop of the coalfield over a period of at least five thousand years, but possibly ten thousand.
The site is not protected by any statutory legislation; it is however, a registered "Regionally Important Geological Site" or RIGS and a Grade II listed building site." Text Source: (
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