Tobergortnaun, in the townland of Claggan on the Atlantic edge of County Mayo, contains the Irish word tobar, meaning a well, most likely a holy well of the kind that dots the Irish landscape in their thousands. These sites, often little more than a stone-lined spring with a rough surround, carry layers of pre-Christian and early Christian devotion simultaneously, frequented for centuries by people seeking cures, offering rags or coins, and observing patterns, the local ritual circuits and prayers performed at specific times of year, often around a saint's feast day.

Beyond its name and its place on the map, the particulars of this site remain largely undocumented in any accessible public record at present. What can be said is that Claggan sits in a part of Mayo where the land meets the sea in complicated and often spectacular ways, and where the density of archaeological and folkloric sites is considerable. Holy wells in such areas were frequently associated with local saints whose cults never spread far beyond a single parish, their stories surviving mainly in oral tradition or in the occasional manuscript note rather than in any formal hagiography.