At the mouth of the Cashen river in north County Kerry, a fulacht fia, one of Ireland's most common yet least understood prehistoric monument types, was recorded along the shoreline roughly two decades before the site was uploaded in 2013, and has since been entirely consumed by erosion. Nothing remains to visit.

A fulacht fia, sometimes called a burnt mound, is typically a horseshoe-shaped mound of fire-cracked stones accumulated beside a water source. The working theory, supported by experimental archaeology, is that stones were heated in a fire and dropped into a water-filled trough to bring it to the boil, with uses ranging from cooking to hide-working to bathing. They are found in their thousands across Ireland, most dating to the Bronze Age. The Ayle example was noted as a spread of burnt stones along the shoreline, which suggests the mound component, if there ever was one, had already been lost or dispersed before it was first recorded. Coastal and riverine locations are especially vulnerable; the Cashen meets the sea in an exposed stretch of north Kerry, and the combination of tidal action and storm erosion can dismantle even substantial earthworks over a relatively short period.

What makes this particular record worth pausing over is not what survived but what the disappearance illustrates. The site was catalogued in C. Toal's North Kerry Archaeological Survey, published in 1995, at a point when erosion was already well advanced. Within a generation, it was gone entirely, leaving only the note itself as evidence that something prehistoric once lay at that waterline.