The city was divided into distinct, separately walled zones, and the area known as the Hightown had its own boundary walls, fragments of which have survived in unexpected corners of the modern streetscape. One such fragment, associated with a structure known as Talbot's Tower, represents what remains of a defensive system that once enclosed one of Ireland's most heavily fortified medieval urban centres.

A 15th to 16th-century stretch of the Hightown's town wall was recorded by archaeologist Cóilín Ó Drisceoil on the southern bank of the river Breagagh, at No. 6 Watergate Street. Town walls of this period were typically built in mortared stone, punctuated at intervals by mural towers that allowed defenders to cover the face of the wall with flanking fire. Talbot's Tower is one such surviving feature associated with this defensive circuit. A further section of walling is visible in profile on Abbey Street, where an east-facing section reveals the construction technique and something of the wall's original mass. The Breagagh, a small river that formed a natural boundary on one side of the Hightown, would have been integrated into the defensive logic of the whole arrangement, with the wall running along its bank to close off approaches from the water.

The wall section on Watergate Street and the Abbey Street profile are both embedded in the fabric of existing buildings and streetscapes, making them easy to pass without registering what they are. The tower and the river-side stretch are the most legible survivals, and looking along the south bank of the Breagagh gives some sense of how the wall once used the watercourse as part of its line.