It is not much to look at from above, but what sits beneath the surface is the remnant of a fulacht fia, one of the most common and most quietly puzzling monument types in the Irish archaeological record.

Fulachtaí fia (the plural form) are ancient cooking sites, found in their thousands across Ireland, and most date to the Bronze Age, roughly 1500 to 500 BC. The typical arrangement involves a trough dug into the ground, a nearby water source, and a mound of fire-cracked stone that built up over repeated use. The method was straightforward: stones were heated in a fire, dropped into a water-filled trough, and used to bring the water to a boil. Over time, stones that had shattered from repeated heating were discarded into the characteristic horseshoe-shaped mound that survives at so many sites. At Glancam, the spread of burnt material measures roughly ten metres in one direction and twelve in the other, which places it within the typical size range for such sites. The waterlogged ground recorded to the east of the spread is significant; proximity to a reliable water source is a near-constant feature of these monuments, and the boggy conditions that so often preserve them are also what originally drew people to build them there.