At the eastern foot of Cappanawalla Hill in County Clare, on a south-facing slope of improved pastureland, the Ordnance Survey maps of both 1840 and 1915 mark a feature simply labelled "cave". It sits within a cashel, the kind of dry-stone enclosure, typically circular, that was used in early medieval Ireland to define a farmstead or small settlement. The cave was recorded twice across three quarters of a century of cartographic work. Then, by the time anyone went looking in earnest, it had vanished.

When the site was inspected in 1997, no visible trace of the cave remained. What survives is the cashel itself, and within its interior there are signs of disturbance, ground that has been dug out or otherwise disturbed in a way that may explain the absence. Whether the cave was a natural hollow, a souterrain (an underground passage associated with early medieval settlements, often used for storage or refuge), or something else entirely is no longer clear. It was absent from the Sites and Monuments Record of 1992 and the Record of Monuments and Places of 1996, meaning it slipped through successive layers of formal protection without ever being properly assessed. The two OS maps remain the most concrete evidence that it existed at all.