Somewhere beneath a rectangular enclosure at Tipper in County Kildare, a souterrain lies largely out of reach, its course now readable only as a shallow groove in the ground. A souterrain is an underground stone-built passage or chamber, typically constructed in early medieval Ireland for storage or as a place of refuge, and the one at Tipper was still just about accessible within living memory, though it has since been swallowed by time and collapse.

In the 1930s, local knowledge held that you could enter the structure through a hole in the stone-lintelled roof of an eastern chamber. Moving westward from there, a second chamber opened up, and beyond it a narrower passage that was already blocked, possibly the original entrance through which people had once ducked in and out. By 1972, entry was no longer possible at all. What remained visible above ground was a depression in the north-west corner of the enclosure and a second, longer depression running north to south through the interior before turning to follow the line of the enclosing bank along the south, then bending again to run a short distance westward. That shallow trace in the earth, roughly 0.4 metres deep and averaging about 2 metres wide, suggests a souterrain that has been partially robbed out, its stones likely lifted and repurposed at some point, leaving the ground above to settle into a tell-tale sag.

The enclosure in which it sits adds another layer of interest. Rectangular enclosures of this kind are not the most common field monument in Ireland, and the combination of enclosure and souterrain hints at a settlement of some significance, though without further excavation the relationship between the two features remains a matter of inference rather than record. The depression itself apparently still survives, quietly marking out the ghost of a structure that, within a few generations, moved from a known entry point to an inaccessible curiosity to little more than a crease in a field.