This is the only thermal well in Wales, at about 19 degrees C, as well as being a mineral spring, the copper giving it a green tinge, and the iron a dark red. Bubbles rise steadily to the surface.
There were once something like 1800 holy wells in Wales, including one on the island of Flat Holm in the Bristol Channel, many of which have been lost or built upon; it is unknown whether this was one of them. Its present name is from its proximity to the River Taff, to the north of Cardiff.
My book on holy wells in Wales describes a number of others that had bath houses like this one, suggesting there were more thermal springs, but officially there are only 4 in Britain. Bath is the most famous of course; its water is 46 degrees Centigrade, Bristol’s Hotwells are 24, Llandroid Wells in Wales are a mere 14.
Geologist claim the water that springs here is from nearby hills, and they have dated it as having taken between 8 and 11,000 years to reach the surface here. I really struggle to comprehend how water can move that slowly, but I am not a geologist.
People used to drink several pints of this stuff each day, but we are not allowed to touch it – health and safety of course – the same is in Bath, though you can drink the water at Cheltenham Spa if you are there when the pump room is open. I never have been. I am told it tastes terrible. Probably why it’s supposed to be good for you. At present the well is in an old concrete shed, but locals hope to build something grander, including a swimming pool, as there are still locals who remember swimming in it many years ago.