King Arthur stuck in the mud, returning to but still short of his native Britain, remains for me this volume’s iconic image. At a key moment in the Alliterative Morte Arthure, having defeated the naval forces of Mordred, Arthur finds himself arrested, as Kathy Lavezzo puts it, by ‘oceanic mud’ (p. 131). Occupying neither sea nor land, Arthur momentarily straddles the Old English terms that give us, through the ‘combining [of ] water (ea) and land (land/lond)’ (p. 31), island. Many other key locales in this volume borrow imaginative potency from such meetings of land and water: Maldon, Chester, Lindisfarne, and even Mont St Michel. Indeed, the phenomenon of the tide proves so potent here as to command an entire chapter from Catherine Clarke. After-effects of tides upon marine landscapes reveal the imaginative beggary of our modern terms mud and sludge: ‘thane was it slyke aslowde in slakkes full hugge,’ says the Alliterative Morte of the mudflats; it is pleasing to observe, with Lavezzo, the suggestive alchemy of these terms defeating modern editors. And is worth noting that the Bristol Channel, in draining the Severn and the whole heartland of the Arthurian world, experiences the world’s second greatest tidal variation, producing great landscapes or seascapes of slyke.

Chaucer’s Shipman knows how to pick his way along the challenging coastlines of Brittany and Galicia, navigating creeks where abrupt transitions between rock and water call for expert local knowledge (1.407–09). There are maps and charts, Alfred Hiatt shows, to facilitate such coast-hugging navigation; there are other kinds of maps to help plan open-sea voyaging; and there are cosmological aids, mappae mundi and illustrations from Macrobius, to pilot yet grander travels. We should not think such generic distinctions of mapping to be water-tight: portolan charts, for example, carry over information from mappae mundi; and locations deep inland feature regularly on maps ostensibly designed to aid coastal navigation. Pragmatic and religious ends, Hiatt argues, often shared medieval mapping spaces: merchants at sea might seek the Holy Sepulchre, and land-tied monks might locate Genoa in relation to Cyprus (p. 153). Hagiographies and romances often ply the same oceanic spaces, observing distinct generic rules.