In early medieval Ireland, people built and lived on small islets o f stone, earth and wood situated in the watery shallows o f lakes. These artificial islands, known to modem scholars as crannogs, are amongst the most remarkable and evocative features of the Irish archaeological landscape, mysterious, tree-clad islands often situated on isolated lakeshores. Over the years, Irish crannog studies have waxed and waned, but their contribution to our understanding of the past has been immeasurable. Since the nineteenth century, they have been the focus of antiquarian and archaeological investigation, and various twentieth-century archaeological excavations have revealed evidence for their form, structures, houses, pathways, fences, pits, working areas, and the debris of crafts, domestic activity and industrial production. Archaeological surveys have indicated their diversity of size, morphology, siting and location, while also producing literally thousands of objects from their wave-eroded surfaces.