The rath at Carncash, Co. Sligo, is modest in scale, yet it has held on to enough detail to reward a careful look. The enclosure is nearly circular, measuring roughly 21 metres north to south and 22 metres east to west, and the earthen bank that surrounds it still carries a respectable external height of about 1.27 metres, even if the interior face has settled considerably lower over the centuries.

Raths, the most common monument type in Ireland, were typically the enclosed homesteads of early medieval farming families, dating broadly from the fifth to the twelfth century. The bank here is about 2.6 metres wide and retains visible revetment stones on its south-eastern arc, where large flat stones arranged in a regular course once reinforced the structure from the inside. Revetment of this kind, where a facing of stone was used to stabilise an earthen bank, is a feature that implies some care in the original construction, even on a site of this size. What the rath does not have is a fosse, the external ditch that normally accompanied a bank of this type, and there is no surviving trace of an original entrance gap or causeway. At the south-west, a spread of quarrying roughly six metres wide has disturbed the bank, which accounts for some of what is missing.

The site sits in gently rolling pasture adjoining a farmyard, and the surrounding land remains agricultural. The low bank blends easily into the field boundary landscape, which is partly why such places pass unnoticed. The revetment stones visible at the south-east are the most concrete detail to look for, their regular setting standing out against the general earthwork.