Although now home to three caving clubs, South Wales CC, Swindon SS, and Wealden CMS, Penwyllt also has a fascinating past. Around the village can be found the evidence of early tramroads, lime-burning, brick-making, and the Neath and Brecon Railway as well as the physical infrastructure of the close-knit former working community. The book describes these various facets of Penwyllt, as well as an overview of the geology, landscape and caves.