That much is recorded. Beyond that, the details dissolve into the city that subsequently buried them, built over them, and forgot them entirely. No map pins them down, no surviving structure marks the spot, and the ground they once occupied has long since been absorbed into one of the most heavily developed urban cores in Ireland.

The historian Clarke, writing in 2002, notes the former existence of fishponds or weirs in the vicinity of Dublin Castle as of 1587. Fishponds of this kind were a practical feature of medieval and early modern institutional life, essentially managed enclosures of water used to keep live fish as a reliable food source, particularly useful for observing the many fast days in the Catholic and later Protestant calendars. A castle complex the size and importance of Dublin Castle would have required considerable provisioning, and a controlled water feature of this kind would have been a reasonable part of that infrastructure. Weirs served a related but slightly different purpose, using the flow of a river or stream to trap fish rather than simply containing them. The proximity of the Poddle river, which once ran more openly through this part of the city before being progressively culverted, makes the location plausible enough, though Clarke is careful not to assign precise coordinates.

There is, practically speaking, nothing to visit. The site is unlocated, and the ponds themselves left no known trace above ground. What the record offers instead is a small corrective to the tendency to think of historic Dublin as defined only by its surviving stone. The Castle ward and its surroundings supported a working economy of food, water, and labour, most of which has vanished without ceremony. If you happen to be walking the streets south of the Castle, around the area where the ground dips slightly toward where the Poddle once ran, it is worth pausing to consider what the city covered over in its long process of becoming itself.