It may be a ruined lime kiln, a structure once used to burn limestone and produce quicklime for agriculture and building, though whatever its original purpose, it now sits quietly at the foot of an early medieval enclosure that has itself been half-absorbed by the working landscape around it.

The enclosure is a rath, a type of ringfort typically associated with the early medieval period in Ireland, constructed as a defended farmstead for a family of some local standing. At Carrowcanada it takes a slightly oval form, measuring roughly 23 metres north to south and 27 metres east to west, defined not by an earthen bank but by a scarp, a sharp drop in ground level that varies considerably in height around the circuit. On the eastern side the scarp is only about 0.4 metres high, but on the southern side it reaches two metres, assisted there by the natural fall of the ridge on which the rath sits. That ridge position was clearly deliberate; the ground drops away steeply to the south, which is also where the views are best. The western stretch of the scarp has been incorporated into a later field fence running roughly north-northeast to south-southwest, and the remnants of another fence merge with the scarp at the north, suggesting that whoever laid out the post-medieval field system here found the old earthwork a convenient boundary and built accordingly. Inside, the surface is uneven, dipping slightly in the north and sloping down towards the perimeter in both the southeast and southwest quadrants. Hawthorn, gorse, and brambles have colonised the perimeter and are advancing into the southwestern interior, gradually obscuring the contours that give the site its character.