That it had gone unrecorded for so long is partly explained by its setting: the ring-barrow sits in a low-lying basin, with higher ground rising around it on all sides, effectively screening it from casual observation. A ring-barrow is a funerary monument of prehistoric date, typically consisting of a central mound enclosed by a circular ditch and, often, an outer earthen bank. The Jeffrystown example follows that pattern, though time and agricultural activity have taken their toll. The central mound, which measures roughly 33 metres across, now sits below the level of the surrounding ground rather than above it, and rubble has been dumped into the ditch's south-eastern quadrant at some point in recent times. What was once a substantial monument has been reduced to something that requires a careful eye, or an aerial photograph, to read properly.

When surveyor David McGuinness measured the site in 2015, the outer ditch proved to be broadly U-shaped, with a basal width of 2.7 metres and, on its north side, sunk 0.78 metres below external ground level. The faintest traces of an outer bank survive, though these are so indistinct they were excluded from the overall diameter measurement of 44.5 metres north to south and 47.2 metres east to west. The monument does not stand alone in the landscape. A second circular earthwork, possibly another barrow, is visible on aerial photographs in an adjacent field roughly 60 metres to the west-north-west, though it had not been examined on the ground as of the 2015 survey. Less than 350 metres to the south-east, in the townland of Edmondstown, lies a further barrow, and between the two sites sits a small lake or pool, possibly a kettle-hole, a depression formed by the melting of a buried block of glacial ice. A small stream, its channel altered in places for drainage, runs between the lake and the Jeffrystown barrow. About 700 metres to the north-west, in Balreagh, the landscape acquires a further layer of history: a ruined medieval church within a burial ground whose regular oval enclosure led the scholar Leo Swan, writing in 1988, to identify it as an early medieval ecclesiastical foundation. Immediately adjacent to the church site is a motte, the earthen mound at the core of a Norman fortification, and close by is a souterrain, an underground stone-lined passage associated with early medieval settlement. The prehistoric barrow, then, sits within a corridor of monuments stretching across more than a millennium of human activity in this quiet corner of Westmeath.