St. Martin's Lane, running off Werburgh Street in Dublin's south city, is one such trace, a quiet topographical footnote marking where a church once stood, was absorbed into a neighbour, and eventually disappeared altogether, leaving its name snagged in the street map like a thread caught on a nail.

St. Martin's medieval parish church stood to the north of what is now St. Werburgh's Church of Ireland, and was assigned to the Chancellor of St. Patrick's Cathedral, giving it a modest but real place in the administrative machinery of medieval Dublin. By 1219 to 1220, it had been absorbed within St. Werburgh's, a fate that suggests diminishing congregations or shifting parish boundaries rather than any dramatic event. Remarkably, the remains of the old structure were said to be still visible as late as 1529, more than three centuries after its effective dissolution. St. Werburgh's itself went on to accumulate chapels dedicated to St. Martin, Our Lady, and St. Catherine during the sixteenth and seventeenth centuries, and was enlarged in 1662 with a square tower added to the east end. The building was then substantially rebuilt between 1715 and 1719 to designs by Colonel Thomas Burgh, who was also the architect of the Long Room Library at Trinity College Dublin, and the façade facing Werburgh Street dates from that phase of work. In the eighteenth century, burials uncovered on the western side of Werburgh Street were believed to belong to an earlier cemetery associated with St. Martin's, a reminder that the ground beneath city streets often holds more than the streets themselves suggest.

St. Werburgh's Church stands on Werburgh Street, close to Dublin Castle, and is accessible on foot from the city centre. The church itself has an eventful history of its own and is occasionally open to visitors, though opening times vary and it is worth checking ahead. St. Martin's Lane remains findable off Werburgh Street, a short and easily overlooked passage that carries no particular marker of its medieval significance. Those interested in the layering of Dublin's ecclesiastical past might find it worth pausing there, if only to note how thoroughly a parish church can vanish while leaving just enough behind to be remembered.