This chapter “examine[s] the encounter between Irish literature as a ‘terrestrial form of thought,’ and the ocean as a putatively alien environment.” John Brannigan draws on a host of Environmental Humanities scholarship, most specifically from Blue Humanities; his reading treats the oceanic as a critical and material space providing alternative epistemologies to humanity’s dominant land-based knowledge systems. In the “encounter with the maritime” such terrestrial thinking “would find a scene of negation, radical otherness, or utopian or dystopian release.” The chapter begins with an important reminder of “The Real Map of Ireland, a dataset resulting from the Irish National Seabed Survey which mapped the 220 million acres of “land under the sea” over which Ireland is entitled to claim sovereignty and “exclusive economic rights” under the United Nations Convention on the Law of the Sea (UNCLOS).” This new submarine “territory” that extends to almost a thousand kilometers across the Atlantic Ocean and the Maury Channel, and to the south over three hundred kilometers, Brannigan argues, “marks a submarine treasure map” and is open to capital’s inexhaustible extractive appetite.