The detail comes from a single mention in J.W. de Courcy's 1996 work on the River Liffey, and it is telling precisely because so little else is known. No plan survives, no precise location has been established, and the earthwork itself has long since vanished beneath whatever the city chose to build next. What we are left with is a name, a hillside, and a probable function.

Lazar's Hill took its name from the leper hospital that once stood in the vicinity, a common enough feature of medieval urban edges, where institutions caring for the infectious were placed at a deliberate remove from the population centre. By the seventeenth century the hill had shed that association and become part of the busier approaches to Dublin from the south. De Courcy suggests the 'forte', an earthwork in this context meaning a defensive or controlling enclosure formed from banked earth rather than stone or timber, may have functioned as a customs post. That would make a degree of practical sense. Roads converging on a city gate were natural chokepoints, and a physical structure at such a position could regulate the movement of goods, levy tolls, and assert civic or crown authority over traffic coming in from the counties to the south. Earthwork fortifications of this kind were relatively cheap and quick to construct, which also made them relatively easy to demolish or simply to let erode.

Because the site has not been precisely located, there is no specific spot a visitor can stand and say with confidence that this is where the 'forte' was. The area around what is now Townsend Street and the south-east approaches to the old city is the broad neighbourhood in question. For anyone interested in the lost topography of early modern Dublin, the interest lies less in finding a physical trace, which is almost certainly gone, and more in reading the present streetscape against what the maps and documents suggest was once there. De Courcy's work remains the starting point, and the Dublin City Council archaeological archive may hold further references for those prepared to look.