At An Fhaiche in County Galway, an oval enclosure once sat in what is now reclaimed pastureland, and the only reliable record of its existence is a mark on a nineteenth-century map. No earthwork, no ridge, no shadow in the grass remains to suggest anything was ever here at all.

The Ordnance Survey six-inch map of 1899, produced during the second edition revision, recorded the enclosure as an oval roughly forty metres along its north-south axis and thirty metres east to west. Enclosures of this general type, typically defined by a circular or oval bank and ditch, are among the most common archaeological features in the Irish landscape, and many are associated with early medieval settlement, though without excavation it is rarely possible to say more than that. What makes this one worth noting is precisely that land reclamation has erased it entirely. The process of draining, levelling, and converting boggy or marginal ground into productive pasture has, across many parts of Connacht, quietly removed features that survived for centuries under rough grazing or scrub. The map caught it just in time, or nearly so.