St. Martin's Chapel left no visible trace above ground, yet its absence is oddly telling. It once gave its name to St. Martin's Lane, a short passage between the church and Castle Street that itself vanished during the eighteenth century, taking the last legible sign of the chapel with it. A building, a lane, a name, all gone in sequence, leaving only the records behind.

The chapel was a proper freestanding structure, not merely a screened-off corner of the main church, but a separate building attached to the north side of the chancel of St. Werburgh's. Its counterpart, the Lady Chapel, stood to the south. Each was lit by a single window and had a tiled floor, strewn with rushes on special occasions. A statue of St. Martin stood not in a wall recess but on a bracket or throne fixed to the wall at the east end. The churchwardens' accounts, published by J. L. Robinson in 1914 in the Journal of the Royal Society of Antiquaries of Ireland, preserve a handful of telling details: a payment of twopence for rushes on Martinmas Day in 1510 to 1511, thirteen shillings for making the saint's throne around 1520, and eleven shillings for repairing the chapel wall between 1567 and 1570. The chapel had already been burnt down once, in a great fire that swept through Dublin City in 1311, and was presumably rebuilt thereafter.

There is nothing to see at the site itself, which is part of what makes it worth knowing about. St. Werburgh's Church still stands on Werburgh Street, and a visit there rewards attention, but the northern side of its chancel offers no clue to what once adjoined it. The value here is less in the ground than in the documents, particularly Robinson's transcription of the churchwardens' accounts covering 1484 to 1600, which preserve the texture of parish life in medieval Dublin with unusual specificity. For anyone interested in how the city's layers have been quietly buried rather than dramatically demolished, the non-site of St. Martin's Chapel is a useful place to stand and think.