Cook Street, running along the south side of the old city near the line of the medieval walls, holds exactly this kind of absence. At its western end, on the southern side, a house is recorded that leaves no visible surface trace whatsoever, its existence preserved only in scholarly notation and a specialist map.

The house appears on the Friends of Medieval Dublin Map, produced in 1978 as part of an effort to document the surviving and recorded remains of the city's medieval built environment before further development could erase the evidence. It is also cited by Bradley and King in their 1987 survey of medieval Dublin, catalogued as entry number 139 in the third volume. Cook Street itself was a significant thoroughfare in medieval Dublin, running close to the city's defensive circuit, and the area around it was densely settled during the later medieval period. The street takes its name from the cooks and food traders who operated there, a common pattern in medieval urban naming, and properties along it would have formed part of the commercial and domestic grain of the walled town. Beyond the map reference and the catalogue entry, the record offers nothing further: no owner, no date of construction, no description of form or materials.

For anyone curious enough to seek out the spot, Cook Street is easily reached on foot from Christchurch Cathedral, heading roughly westward. The western end of the street meets Nicholas Street and the area around the old city walls. There is nothing to see at the specific location, which is rather the point. What makes such a record worth pausing over is the way it holds open a question that the streetscape itself has long since closed. The 1978 map was produced precisely because scholars recognised that the medieval city was at risk of being built over without adequate documentation, and entries like this one represent the thinnest possible thread of evidence, a dot on a map and two lines in a footnote, connecting the present street to a house that once stood here and whose inhabitants remain entirely unknown.