It is a fulacht fia, a type of monument found in considerable numbers across Ireland, most commonly dating from the Bronze Age. The prevailing interpretation is that these were outdoor cooking sites: stones were heated in a fire and then dropped into a water-filled trough, bringing the water rapidly to a boil. Over successive uses, the fire-cracked, spent stones were raked out and piled up around the trough, forming the horseshoe-shaped mound that survives today. The wet ground around Bolintlea would have suited the purpose well, providing a reliable source of water close to the surface.

This particular example is notably large, measuring roughly 18 metres north to south and 18.5 metres east to west, and rising to a maximum of about 0.7 metres above the surrounding ground. In the northern quadrant of the mound there is a shallow depression, around 1.3 metres by 1.2 metres and 0.35 metres deep, which is thought to indicate where the original trough once sat. There is no formal opening or gap cut through the mound edge, as is sometimes seen at other fulachta fia, but the mound is noticeably lower in that northern quadrant, with the edge of the depression sitting roughly 6.5 metres from the mound's base. Thirty metres to the north lies a separate and distinct monument, a moated site, where a medieval dwelling would once have occupied a raised platform surrounded by a water-filled ditch. The proximity of the two monuments, separated by many centuries of use and purpose, gives the landscape here an unusual layered quality.