At Mullaghroe in County Kildare, there is a site that has, in a sense, ceased to exist twice: once in the ground, and once on paper. A ringfort, or rath, was a circular earthwork enclosure common across early medieval Ireland, typically consisting of a raised bank and an outer ditch, known as a fosse, used to define a farmstead or dwelling. What survives at Mullaghroe is neither of those things, but rather the paper trail of a disappearance.

The site does not appear on the first edition Ordnance Survey six-inch map from 1838, suggesting it was already inconspicuous or unrecognised at that point. By the time of the 1939 revision, however, cartographers had noted a curving raised area in the north-west quadrant of what appeared to be a circular feature with an estimated radius of around forty metres, situated just north of a zone of quarrying, on the lower slope near the foot of a short, moderately steep-sided pasture ridge. That partial outline is all the map record ever captured. Local accounts indicate that the bank and fosse were levelled around 1960, and by a survey carried out in 1972 the earthwork had been reduced to almost nothing, with only faint traces of the fosse still visible along the western side. Today, no surface trace of the fosse remains at all, and the site is classified with the cautious qualifier that it may have been a ringfort, the ambiguity itself a consequence of its destruction before any thorough examination could be made.