It is not a dramatic ruin in any conventional sense. There is no tower, no stonework reaching skyward, no obvious centrepiece. What remains is a low bank of earth and stone, measuring just over a metre wide and less than a metre high on either face, enclosing a wet and uneven interior perhaps 27 metres across at its widest. The field boundary that slices through it from the south-west to the north represents precisely the kind of quiet, incremental erasure that has removed hundreds of similar monuments from the Irish landscape without anyone particularly noticing.

This is a rath, a type of enclosed farmstead built predominantly during the early medieval period in Ireland, roughly between the fifth and twelfth centuries. Raths were typically circular or oval enclosures defined by one or more earthen banks and ditches, and they served as the domestic and agricultural centres of single farming families or small kin groups. They are among the most common archaeological monument types in Ireland, yet the majority survive only partially, their banks reduced by centuries of ploughing, grazing, and boundary-making. The Derrysallagh example is modest even by these standards: its internal dimensions suggest a relatively small enclosure, and the bank itself has been significantly reduced, leaving heights of under a metre where once there would have been a more substantial barrier. The overgrowth of bushes, while obscuring the form, has also likely helped to stabilise what survives.