Located in County Limerick, this site has witnessed multiple transformations; from a medieval castle to a grand house, and finally to the farmhouse remnants visible today. The original Kilcosgrave Castle, whose foundations can still be traced near the current structure, was already established by 1299 when it was held by the heirs of W. Roth under the Fitzgeralds. Historical records paint a vivid picture of medieval life here, including the rather charming detail that the castle's rabbit warren was plagued by foxes.

The castle changed hands numerous times throughout its history, passing through the powerful Earls of Desmond in 1452 before being granted to William Trenchard in 1587. By 1611, his son Francis had inherited the property and leased it to Richard Gyll, with records noting it was still "a sufficient dwelling" at that time. The property's fortunes took an interesting turn through marriage; Francis's daughter wed Captain J. Coplen, and their son John married Susanna Langford in 1677. When John died in 1719, he left the estate to his wife's nephew, establishing the Langford family's long residence at Kilcosgrave.

By 1840, when the Ordnance Survey documented the site, the original castle had vanished from living memory, though its foundations remained visible. The Langfords had erected a rectangular house on the castle's footprint, which itself had partially fallen into ruin by that time, with only a portion converted for use as a farmhouse. This layering of structures, each built atop the bones of its predecessor, makes Kilcosgrave a fascinating example of how Irish estates evolved and adapted through centuries of political and social change.