Located in the Brecon Beacons
The distillery sits above a cavernous aquifer that contains rock formations laid down around 340 million years ago.
This aquifer holds water that filters down through the overlying basal grit into the limestone. The whole formation is described as thick-bedded and of fine to course-grained material. It was originally deposited in a shallow marine environment. Ancient weathered surfaces exist in parts of the formation, covered with thin, primordial soil in places where the rock was briefly higher than sea level before being submerged again.