The wall known as the Lynch Memorial, or the Lynch Window, is a deliberate collage: fragments from five old windows and two doorways, a keystone from a fireplace lintel, and various other salvaged pieces were gathered and composed to resemble a house façade. The whole thing was purpose-built to provide a suitably solemn home for a small, older stone already embedded in local legend. That stone, a gable-shaped piece dated 1624 and carved with a skull and crossbones, carries the inscription "remember deathe vaniti of vaniti & all is but vaniti", a rendering of the Old Testament epigram from Ecclesiastes, of the kind commonly found on gravestones of the period. It is a genuine seventeenth-century memorial. The medieval house it purports to belong to is not.

The story behind the monument reaches back to 1493 and the mayoralty of James Lynch fitz Stephen, who according to Galway tradition condemned and hanged his own son Walter for murdering a foreign guest, carrying out the sentence himself when no one else would act. The tale, first set down in the seventeenth century, attached itself over time to a house on this spot, which by the early nineteenth century was known locally as the Crossbones, presumably on account of the 1624 plaque set above its door. When the building was demolished in 1844, the plaque was carefully preserved. A decade later, with the backing of the Town Commissioners and their chairman, the Very Reverend Peter Daly, the fake façade was built around it, and an inscription panel added to explain the legend. The trouble was that it worked rather too well. Within a generation, people were treating the assembled stonework as a genuine medieval survival, and the upper window was being pointed out as the very spot from which Walter Lynch was hanged. The monument circulated in guidebooks and local accounts as authentic history until the story was subjected to serious scrutiny in the late 1960s. No evidence connects the 1624 carving, the house, or the site to the Lynch family or the events described. Among the genuinely old fragments incorporated into the wall is a fireplace keystone bearing the impaled arms of the Lynch and Browne families, flanked by the initials GL and EB, probably dating to the first half of the seventeenth century, which at least confirms that the salvaged pieces came from Galway merchant households of some standing. In 1978, the whole structure was dismantled, given a concrete backing, and set slightly away from the pavement to allow it to be seen clearly, with two flanking walls linked to the churchyard boundary by pillars that had formerly served as gate piers to the graveyard beside it.