At the highest point of the mountain pass through the Knockmealdowns, wedged between the peaks of Knocknafallia to the west and Knocknasheega to the east, there are the remains of a constabulary barracks, a police outpost placed precisely where it would be most exposed and most visible. The location is not incidental. Whoever garrisoned this place was stationed not in a town or village but at the top of a mountain road, watching the pass itself.

By 1837, when the Ordnance Survey published its six-inch map of the area, the structure was already recorded as a Constabulary Barracks, placing its construction in the early decades of the Irish constabulary system, which was being formalised and expanded across rural Ireland during the 1820s and 1830s. What survives is a rectangular walled enclosure, roughly fifteen metres north to south and just over ten metres east to west, built from masonry with cut-stone quoins at the corners. The walls still stand to around two metres in height, with a thickness of about sixty centimetres. The barracks itself was arranged along the southern and northern sides of this internal courtyard. The southern building retains a fireplace in its west gable wall and was presumably where the men were quartered; the northern building, less finished in character, may have served as a stable. The original large windows in the southern building have been reduced at some point to narrow openings, a modification that changed both the light inside and, perhaps, the sense of exposure from without. Entry to the southern building was through a doorway in its south wall, while a separate opening in the west wall gave access to the courtyard between the two ranges.

The site sits on the east side of the road as it crests the pass, which means anyone travelling this route in either direction would have passed directly alongside it. In a landscape with very little cover and considerable elevation, the building would have been hard to miss and harder still to approach unnoticed, which was almost certainly the point.