Henrhyd Falls (Welsh: Sgwd Henryd) are renowned for being, at 27m/90ft , the highest in South Wales. They are at their most impressive when the waters of the Nant Llech are swollen with recent rain. At other times, the flow can be considerably reduced. During times of prolonged frost such as the winter of 2010/11 they can freeze up almost entirely and are again worth a visit though approaching closely can be hazardous.
The falls occur where the river crosses the Henrhyd Fault and drop over a caprock of the 'Farewell Rock' into a gorge cut in less resistant mudstones. A gully below the steep access path betrays the position of the fault, the falls having retreated upstream somewhat since their inception.
Both Henrhyd Falls and a kilometre stretch of the gorge below are in the care of the National Trust who have provided a car park just above the falls.
Tawe Uchaf Community Council worked with the Trust and the national park authority to install an audio trail down the gorge relating aspects of its history and natural history.