These structures, typically built partly or wholly underground to exploit the insulating properties of earth and stone, were used to store blocks of ice harvested in winter from nearby lakes, rivers, or specially flooded ponds. Packed tightly with straw or sawdust, the ice could last well into summer, keeping game, fish, butter, and other perishables cold for months. The icehouse at Claremount in County Mayo is one such survival, a quiet reminder of how the management of an estate household once required considerable ingenuity and forward planning.

Claremount is a country house estate in Mayo, and its icehouse is the kind of feature that rarely draws attention in its own right, easily overlooked in favour of the main house or more obviously dramatic landscape elements. Yet these structures represent a very particular moment in domestic and agricultural history, when the cold chain depended entirely on seasonal labour, good construction, and careful siting. Icehouses were often positioned close to a water source and shaded by trees or an embankment, keeping the interior temperature as stable as possible. The thick walls, vaulted or domed chambers, and drainage channels built into their floors were all carefully considered features rather than incidental details.