In the eighteenth century, cold water bathing, largely for medicinal purposes, became increasingly popular, and this trend was accelerated and transformed by the Romantic cult of wild nature. Swimming was now deemed productive of a range of bodily, mental, and spiritual pleasures; at the same time, it was a source of anxiety on multiple grounds and held a transgressive potential. This essay provides an overview of the popularisation of swimming in the late eighteenth and early nineteenth centuries in the face of a largely fossilized instructional literature, considers its role in the lives of some major Romantic writers (Samuel Taylor Coleridge, John Keats, and Lord Byron), and explores the deepening range of its literary meanings. The essay concludes by making links with the neoromantic wild swimming movement that has grown rapidly in the UK in recent years in response to the overregulation and commodification of aquatic leisure activity.