Tucked into pasture to the northeast of the Glencullen River, this natural spring has been known locally as the Butter Well, a name that points to anxieties far older than any formal record of the place. It is an easy site to walk past without a second thought, which is precisely what makes it worth pausing over.

The Ordnance Survey Letters, a remarkable series of field notes compiled in the nineteenth century as surveyors moved across Ireland documenting local lore and topography, recorded this well as a site reputed to cure stomach and bowel infections, a common attribution for holy or blessed springs across the country. But it was the well's other reported quality that gave it its particular character. According to Daly, writing in 1957 and drawing on older local tradition, the water was believed to offer protection against the loss of butter by witchcraft. The fear of bewitched butter, in which a household's churning would inexplicably fail or their dairy yield vanish to an unseen hand, was deeply embedded in Irish rural belief well into the modern period. A well that could counteract such interference occupied a practical as much as a spiritual role in the lives of people who depended on dairy produce for income and subsistence.

The well sits in pasture and is reached by a laneway off the road to the west of Glencullen crossroads. Glencullen itself is a small upland village in the Dublin Mountains, south of the city, and the surrounding landscape is open and relatively quiet. The site is not formally marked or maintained as a heritage feature, so a visit requires some willingness to navigate farmland and read the terrain carefully. The well is a natural spring rather than a constructed monument, meaning there is no stonework or enclosure to orient yourself by. What you are looking for is the source itself, set into the pasture, with the Glencullen River running nearby to the southwest.