The Tholsel, a structure whose name derives from the Old English for toll or tax hall, was a common feature of medieval Irish and English towns. It functioned simultaneously as a place of civic governance, merchant exchange, and, as the records make plain, confinement. That a gaol should share a roof with the counting tables of city commerce says something about how medieval urban institutions tended to collapse functions that later centuries would keep strictly separate.

The earliest reference to a prison within Dublin's Tholsel dates to 1381, with further detail emerging in 1395, when the building appears to have contained both an upper and a lower level. These details come down to us through the work of John T. Gilbert, the nineteenth-century Dublin historian and archivist whose multi-volume calendar of ancient records of Dublin remains a foundational source for the city's medieval past, and through more recent scholarship by Clarke. The Tholsel itself was not a single permanent structure across this period; Dublin's civic buildings were rebuilt and relocated more than once over the medieval centuries. Precisely where this particular iteration stood, and where exactly within it the prison cells were arranged, is not known. The sources note simply that it has not been precisely located.

Because the site cannot be pinned to a specific address, there is no threshold to stand at or plaque to photograph. What does remain is the documentary trace itself, which is held in the archival and published records of Dublin's civic history. Readers with an interest in pursuing the evidence further might consult Gilbert's published calendars, available in larger research libraries and increasingly in digitised form. The area around the historic civic core of Dublin south city, in the vicinity of the old Christ Church and Wood Quay district, is broadly where medieval administrative life was concentrated, and walking those streets while holding this kind of detail in mind gives the urban fabric a different texture, even if the precise building is long gone.