That absence is itself a curiosity. The mound sits in reclaimed pasture, unremarkable to a passing eye, and yet its flat-topped, oval profile and the faint trace of a surrounding fosse, a shallow ditch that would once have defined its perimeter, suggest something deliberate was placed here long ago. Whether it marks a burial, a boundary, or something else entirely, nobody has yet said with certainty.

The mound was recorded in notes compiled between 1958 and 1961 by O'Dwyer, who described it as an earthen mound measuring roughly 48 feet by 39 feet and rising about 4 feet above the surrounding field level, with a flat top. That description has held up reasonably well. When the Archaeological Survey of Ireland visited in 2007, they recorded a raised oval platform measuring 13 metres north-west to south-east and 8 metres north-east to south-west, consistent with the earlier account. The possible external fosse was noted as visible only at the north-west and north-east edges. The mound sits within a cluster of related features: an enclosure lies 15 metres to the north, and a possible ringfort, a roughly circular earthwork typically associated with early medieval settlement, lies 45 metres to the south-east. A spring marked on the older 25-inch Ordnance Survey map is 38 metres to the south-south-east. The summit of Derk Hill itself, at 782 feet above sea level, is 260 metres to the south-east.

The mound shows clearly in aerial orthophotography from the period 2005 to 2012, but by March 2017 it had reduced to a cropmark on Google Earth imagery, meaning the underlying soil disturbance was visible only through differential growth in the crop above it rather than as a physical rise. This shift suggests the monument has been subjected to continued agricultural pressure over the intervening years. Anyone visiting should approach with that in mind: what was a legible earthwork a decade and a half ago may now be very subtle on the ground. The site is on private farmland on a steep slope, so access would require permission from the landowner, and the terrain demands care underfoot.