Icehouses were the solution adopted by landed estates across Ireland from the seventeenth century onwards: typically brick-lined chambers sunk into the earth, sometimes built into hillsides or shaded by dense planting, where ice harvested from ponds and lakes during winter could be packed tightly and preserved for months into the warmer seasons. The icehouse on the Portumna Demesne in County Galway is one such structure, a quiet survivor of that pre-industrial cold chain that supplied the kitchens and cellars of the great house it once served.

Portumna Castle and its demesne have a long association with the Burke family, later the Earls of Clanricarde, and the estate was among the more significant in Connacht. The castle itself, a semi-fortified house of the early seventeenth century, is well documented, but the functional estate buildings that supported life there, including structures like the icehouse, tend to receive less attention. Icehouses were working infrastructure rather than architecture intended to impress, which is partly why so many were forgotten or allowed to fall into disrepair once their purpose became obsolete.