At Castlecoote in County Roscommon, the remains of just such a structure survive beside the River Suck: an icehouse, probably built in the late seventeenth or early eighteenth century, sitting on low-lying ground roughly ten metres south of an old bridge. Icehouses of this period were typically built into earthen mounds to provide insulation, the surrounding soil holding temperatures low enough to preserve ice cut from rivers or ponds through the warmer months. Here, that protective mound has been removed, leaving the masonry exposed and the spherical chamber partially cut through by a later expansion of the mill-race nearby.

The structure that survives is more complex than a simple pit. At its core is the base of a spherical chamber, around four metres in internal diameter, with walls nearly a metre thick. Attached to its southern side is a vaulted rectangular chamber, roughly four metres by two and a half metres, which connected to the ice-chamber through two small hatches, each less than half a metre wide and about a metre in length. This kind of arrangement was typical: the antechamber allowed access for loading and retrieval while limiting the warm air that entered the cold storage space. The setting itself has deep roots. Sir Charles Coote established a fortified house on this ground after 1616, building on the site of an earlier fortified house associated with a figure named Malby. By the time of the Strafford survey, carried out between 1635 and 1638, a bridge crossing the Suck to the east of the house was already in existence, appearing on a map of Athlone barony. The icehouse came later, a practical addition to what was clearly a well-developed estate complex, though the precise date of its construction is not known.