What was once a substantial oval enclosure, roughly 41 metres north to south and 36 metres east to west, has been reduced over time to little more than a low remnant of drystone wall along its southern edge. The rest has vanished into the ground, leaving a site that asks a great deal of the imagination.

The site is a cashel, the term used for a ringfort whose enclosing boundary was built from stone rather than earthen banks and ditches. Ringforts were the dominant form of rural settlement in early medieval Ireland, typically dating from roughly the sixth to the twelfth century, and many thousands of them survive across the country in varying states of preservation. This one at Carrowconlaun has not fared well above ground, but what remains beneath the surface is more interesting. Within the interior lies a souterrain, an underground stone-lined passage or chamber. Souterrains were commonly built in association with ringforts and cashels, and were used variously for storage, as refuges, or for both purposes. Their cool, stable conditions made them well suited to keeping dairy produce, and their concealed entrances offered a measure of protection during raids.

There is little here to reward a casual visit in terms of visible remains, but the combination of a near-vanished enclosure and a surviving underground feature gives the site a particular quality. The southern wall fragment is the only above-ground indicator of the cashel's original scale, and the souterrain entrance, if locatable, is the one element that hints at the domestic life once organised within this enclosure.