Two stone steps descend from an entrance on the north-west side, wide enough for one person at a time, leading down to the well itself. The opening at the bottom measures just 0.4 metres across, which is to say barely a foot and a half, modest even by the understated standards of such sites. The whole structure, measuring roughly 3.5 metres north to south and 5.2 metres east to west, has the feel of something built with care and then simply left to endure.

The well takes its name from the Irish tobar, meaning a well or spring, and the broader placename connects it to the nearby ecclesiastical enclosure of Killeenaskeagh, which lies to the south-west. A killeen or cillín in this context typically refers to a small church site or burial ground of early Christian character, and the pairing of a named well with such an enclosure is a pattern found across Ireland, where springs were frequently venerated in association with local saints or sacred ground. The two sites share a territorial and probably a devotional relationship, the well serving the spiritual life organised around the enclosure it neighbours.