That it exists at all is the easy part; where exactly it stands is a question that has gone unanswered for well over a century.

The tower appears in Francis Elrington Ball and Everard Hamilton's 1895 historical account of the county, where the authors mention it in passing as a feature of the walls bounding Moreen, a townland in the Balally area of south County Dublin. Watchtowers of this kind were common enough features of demesne and estate walls in Ireland, built to allow a view over surrounding land and to provide a degree of security for the property within. Ball and Hamilton give no precise coordinates, no measurements, and no further description, which has left the structure in a peculiar state of documentary limbo: recorded but not located, noted but never quite pinned down. The reference occupies just a page or two of their text, and nothing more specific has been added to the record since.

For anyone curious enough to go looking, Balally sits in the foothills south of Dublin city, in an area that was largely rural in the late nineteenth century but is now absorbed into suburban Sandyford and Dundrum. The old townland boundaries and estate walls that Ball and Hamilton were writing about have in places survived the development of the intervening decades, and fragments of stone walling can still be found threading between housing estates and along laneways. Whether the tower itself remains standing, was demolished, or has simply been absorbed into later construction is not known. If you do go, it is worth walking the boundary lines slowly and looking at the older stonework carefully; a watchtower could be anything from a projecting turret to a raised corner platform, and without a clearer description it would be easy to pass one without recognising what it was.