The Irish, Tober leath-phingin, translates roughly as "the well of the halfpenny," and the explanation offered by scholar Patrick Power in 1907 is a quietly evocative one: the name arose, he suggested, from the number of halfpenny votive offerings left there by the faithful over the years. The practice of leaving coins or small tokens at holy wells, places where water was held to carry curative or spiritual properties, was common across Ireland for centuries, but a well named directly after the denomination of its offerings is unusual enough to stop you.

The well appears in the Civil Survey of 1654 to 1656, recorded under the anglicised form "Toburnelaffinnyny," a phonetic approximation of the Irish that only barely conceals the original meaning. By the time Power was writing in 1907, it was described as a well formerly much resorted to but still occasionally visited for devotional purposes, suggesting a site already in gentle decline but not yet entirely forgotten. Today there is no visible well structure remaining. What survives is a shallow, stony pool measuring roughly ten metres by twenty, no more than about ten centimetres deep, tucked against a steep cliff of exposed bedrock. The Ordnance Survey six-inch map of 1906 places the well at the north-east corner of that pool, which is now among the most densely overgrown parts of the site. The terrain around it is wet and marshy, the kind of ground that tends to discourage casual visitors and preserve a certain obscurity.