We know this because a revenue map dated around 1694 marks the spot, labelling it 'Brick Kills' in the orthography of the time. Beyond that single cartographic notation, the kilns have left almost no trace, and their precise location remains unknown.

A brick kiln, in its simplest form, is a structure for firing clay bricks at high temperatures until they harden; coastal and estuarine sites were often favoured because suitable clay could be dug nearby and fuel, typically turf or timber, could be brought in by boat. The Clontarf shoreline in the 1690s was a working landscape, and the reference recorded by De Courcy in 1996 places these kilns within a broader picture of small-scale industrial activity along the north Dublin coast during a period when demand for brick was growing in and around the city. The Sheds, which gave the kilns their relative position on the map, were likely storage or fishing structures of the kind that appeared intermittently along this stretch of the bay.

For anyone curious enough to walk the Clontarf foreshore with the question in mind, there is no visible feature to locate, no earthwork or surviving structure to examine. What the site offers instead is the particular experience of reading a landscape against an absence, of standing somewhere along the seafront and knowing that industrious, smoky work was carried out here around three hundred years ago without being able to say exactly where. The revenue map itself, cited by De Courcy, is the closest thing to a fixed point. Local history collections and Dublin City Library archives may hold further cartographic material that could help narrow the location, though so far the kilns have resisted being pinned down.