Somewhere on the Howth peninsula, a building stood during the sixteenth or seventeenth century, significant enough to be noted by the cartographers of its day, yet so thoroughly vanished that its precise location can no longer be determined. No ruin marks the spot. No local landmark carries its name. The structure exists now only as a small mark on an old map.

That map is the Down Survey, produced between 1655 and 1656 under the direction of Sir William Petty, and it represents one of the earliest systematic attempts to map Ireland at a townland level. The survey was carried out in the aftermath of the Cromwellian conquest, primarily to facilitate the redistribution of confiscated Irish land to soldiers and creditors. Its maps are consequently among the most detailed records of mid-seventeenth-century Irish settlement patterns, capturing buildings, roads, and landholdings at a moment of enormous upheaval. The building plotted at Howth appears on this survey, which places its existence firmly within the late sixteenth or early seventeenth century at the latest, though it may well be older. Beyond that single cartographic appearance, the record goes quiet.

For anyone interested in tracing this structure today, the honest answer is that the ground offers nothing definitive to find. The Howth peninsula has been inhabited continuously for centuries, and layers of later development, landscaping, and coastal change have long since obscured whatever physical evidence may once have existed. Researchers interested in the Down Survey itself can consult digitised versions of Petty's maps through the Trinity College Dublin holdings, which allow for close comparison between the seventeenth-century landscape and modern townland boundaries. Walking the peninsula with those maps in mind, and an awareness of where buildings tended to cluster near earlier medieval settlement, may at least give a sense of the probable territory. The absence of a fixed location is itself a reminder of how much of the built past simply disappears, recorded once and then lost to everything except the archive.