At the entrance to what was once known as Hillsboro in Laraghcon, County Dublin, a holy well once stood that local tradition called Sunday Well, a name suggesting the kind of weekly pattern of communal gathering and devotion that once animated hundreds of similar sites across Ireland. Today, a gated entrance and a tree-lined avenue have quietly swallowed whatever physical trace the well left behind. No stonework, no basin, no votive offering survives above ground.

The well is recorded by Ó Danachair in 1958, placing it at the entrance into Hillsboro, which gives at least some sense of how recently it remained part of local memory, even if the physical structure had already begun to disappear by that point. Holy wells in Ireland were rarely elaborate constructions; many were simply natural springs or seeps in the ground, sometimes marked by a stone surround or a nearby tree hung with cloth offerings and small tokens. Their names often reflect the day on which people gathered, the saint to whom the well was dedicated, or some quality of the water itself. Sunday Well fits the first of these patterns, suggesting a site that drew people on a particular day of the week, most likely as part of a pattern of prayer and informal social gathering known as a pattern day, a custom that blended pre-Christian reverence for water sources with later Christian observance.

The location today is west of a row of Victorian cottages, and the gated avenue entrance is the only landmark that corresponds to the recorded site. There are no interpretive signs and nothing to indicate that the ground here once held any particular significance. For anyone curious enough to visit, the experience is less about what can be seen and more about reading a landscape that has moved on. The record compiled by Geraldine Stout and revised by Caimin O'Brien in April 2023 notes plainly that no surface remains are visible, which is itself a useful caution against expecting anything more than a quiet suburban roadside.