Caves form a major element in both scientific and literary writing in the long eighteenth century and function as a crucial part in the transformation of the perception of wild mountain landscapes. Despite this, the role of caves has been critically neglected. This thesis re-examines the writing of this period to uncover the place and importance of caves. From readings of the catastrophic biblical flood, where caves enabled the flood waters to rise and fall from within the Earth, to a far-reaching synthesis of laboratory and fieldwork experiments into the chemical dissolution of limestone, caves attracted wide-spread scientific and cultural appreciation. The role of water in the formation of limestone caves has been the basis for all theories; the major discoveries and advances in knowledge are in how water forms them. Fused with these discoveries, reworkings of mythical descent narratives in poetry, novels and travel journals led to the evolution of a sub-genre in eighteenth-century literature and nascent ideas of the subconscious. The archetypal form of the classical descent narrative is based on the transformative experience of a descent underground and a return to the surface, and this framed the discourses that represented caves and the experiences of descending them, whether they were tangible or imagined. The changing perception of caves was an influence in many scientific and cultural fields, including: knowledge of earth science and the eventual specialization of geology with the assistance of chemistry, the debates over the meaning of nature and god, the development of aesthetic theories and their application to the landscape, and the growth of domestic travel and tourism. The genres of natural philosophy, poetry, prose fiction and travel writing formed the representational discourse of caves through a remarkable degree of dialogue and intertextuality. Those who wrote in this genre blended the causal and the aesthetic understanding of subterranean space before subject specialization would divide them. The representations, instabilities and transformations of this strange subterranean environment are principally illustrated in the writings of John Hutton and William Wordsworth at the end of the long eighteenth century. Their pivotal writings absorbed the material that preceded them and shaped it for the scientific and literary writers that followed. They formed the field of cave and karst science and established the cave as the central metaphor for the creative imagination.