The structure is compact and carefully made: undressed, coursed limestone mortared into walls two metres high, entered through a pointed-arched doorway, with a forecourt to the north containing a line of flagged seating, as though visitors were expected to wait their turn. An alcove built into the western façade, now open to the sky, may once have held a statue, and a rectangular stone trough with a drain-hole sits just to the north-east of the entrance. A cairn-like feature, considerably larger than the wellhouse itself, is built up against its outer walls, suggesting accumulated devotion over a long period.

The well appears on the 1842 Ordnance Survey six-inch map as Tobernacrobaneeve, and by 1977 Tim Robinson's map of the area rendered it as Tobar na Croiche Naoimhe, meaning the well of the Holy Cross. Between those two versions, the 1915 edition recorded something slightly different again, Tobernacrobaneede, hinting at the instability of transliterated Irish place-names across generations of cartographers. As T. J. Westropp noted in 1900, the dedication to the Holy Cross implies that whatever saint was once patron of this parish has since been forgotten, leaving only the Christian symbol itself as a placeholder for a more specific, and now lost, identity. The wellhouse itself dates to the sixteenth century, a period when the formal enclosure of holy wells, those natural springs venerated in Irish tradition as places of healing and pilgrimage, was not unusual in areas under Anglo-Norman and Gaelic lordship alike. A grave slab now built into nearby Gleninagh Lodge, roughly fifty-five metres to the south-south-east, may originally have belonged to this site. A second holy well, Tobar Chornáin, lies about a kilometre to the east, and an ecclesiastical enclosure with a church, graveyard, and associated remains sits approximately two hundred and fifty metres to the south, suggesting that this quiet stretch of the Burren shore once supported a much denser web of religious activity than its present pastoral setting implies.