At Derreen in County Clare, an area of cleared and drained fertile pasture holds what official surveys once catalogued as a possible seventeenth-century house, a structure hedged about with uncertainty from the very beginning. By the time anyone went to look properly, there was nothing older than a modern bungalow to be found.

The site appeared in both the Sites and Monuments Record of 1992 and the Record of Monuments and Places of 1996, each time carrying that careful qualifier: possible. A reference by Weir in 1986 could not even settle on the century, placing the house in either the seventeenth or the eighteenth. When an inspection was carried out in 1998, the earlier structure had left no visible trace. Whether it had been demolished, absorbed into later building work, or simply never existed in the form the records implied is not clear. What remains is a placeholder in the archive, a name attached to a field where cattle now graze on ground that was drained and cleared long ago, and where the historical record ran out of anything solid to say.