The mound at Jamestown, on the eastern slope of Caher Hill in County Limerick, occupies that uneasy category of sites that are simultaneously recorded and lost, documented on paper but effectively gone from the ground.

The Ordnance Survey's six-inch map of 1840 recorded the feature as a raised, roughly circular area defined by a scarp, the term for a steep face or edge formed where ground has been cut or built up. That early survey gave it enough presence to be worth marking. Subsequent editions of the OSi maps dropped it entirely, suggesting that even by the later nineteenth century the mound was fading. When field surveyors returned in 1999, they found a poorly preserved oval mound covered in scrub, measuring approximately eight metres north to south and ten metres east to west. A fosse, the shallow ditch that typically surrounds earthen monuments of this type, was still traceable along the eastern, southern, and south-western arc, with an internal depth of around one and a half metres. The exterior scarp stood just fifteen centimetres above the surrounding ground. By the time Digital Globe and Google Earth orthoimages were captured between 2011 and 2013, no surface remains were visible at all. The record compiled by Fiona Rooney and uploaded in November 2021 relies on that 1999 survey and an accompanying sketch plan drawn by the Archaeological Survey of Ireland.

The site sits in rough pasture to the north-west of a conifer plantation on Caher Hill, which at least provides a navigational anchor for anyone curious enough to look. The plantation edge and the slight eastward slope of the hill are the clearest landmarks. In practical terms, a visit here is less about seeing a monument than about reading a landscape for the faintest traces of one. The scrub cover noted in 1999 may have thickened further, and the low scarp, already barely fifteen centimetres proud of the surrounding ground, is unlikely to register to an untrained eye. Winter or early spring, when vegetation is at its lowest, offers the best conditions for picking out any residual earthwork. The mound's value now is less visual than archival, a small fixed point in the record of how ancient features vanish incrementally, edition by edition, image by image.