This is a bowl-barrow, a type of prehistoric funerary monument built as a round mound surrounded by a quarry ditch from which the construction material was dug, sometimes with an outer bank beyond. What makes the Christianstown example worth pausing over is not just its scale, spanning roughly 37 metres from east to west, but its condition. Bowl-barrows of this size, well-preserved and retaining legible structural detail across the entire circuit, are not commonplace.

When surveyor David McGuinness examined the monument in 2015, he recorded a mound some 17.7 metres across, steeply sided and with a distinct rounded apex that edges it towards conical rather than bowl-shaped. The flat-based ditch surrounding it runs to widths of over five metres on the northern and southern sides. Beyond the ditch sits an outer bank, best preserved on the eastern side where it rises 1.3 metres above the ditch floor. McGuinness also identified a detail that had been overlooked: several boulders protruding from the mound at a consistent height near original ground level, running from the south-east around to the west. He interpreted these as remnants of a retaining kerb, a ring of stones placed around the base of the mound during construction to hold its edges in place. A scattering of larger stones in the ditch itself appear to be later field clearance rather than original fabric. The mound and bank are composed of very stony earth throughout, a fact made visible on the south-south-east side where livestock sheltering under thorn trees have eroded the surface considerably.

The barrow sits on a low rise at the end of a ridge of undulating glacial drift, the kind of terrain left behind by retreating ice sheets. About 90 metres to the south-south-east lies a kettle-hole lake, a small depression formed when a buried block of glacial ice melted, and a second kettle-hole lake lies further to the north-east. The monument is 1.2 kilometres north of the eastern end of Lough Lene and roughly 2.75 kilometres from the early medieval monastery at Fore, a site with its own considerable history. The proximity of these features to one another says something about how this landscape has drawn human attention across very different periods, even if the connections between them are not direct.