The surviving officer's mess, a single-storey limestone building along the south side of the old enclosure, gives little away at first glance, but the marks left on the inside face of the eastern boundary wall, where the ghosts of demolished buildings have pressed themselves into the stonework, suggest how densely occupied this ground once was.

The barracks at Carrignagroghera was built in 1809, and by the time the Ordnance Survey mapped the area in 1842 it had grown into a sizeable complex: a roughly square enclosure of around 225 metres per side, containing three long ranges arranged around an open area, with smaller buildings at the perimeter. Unusually, the western end of the site was at that point designated a Union Workhouse, a function later relocated across the river to the south-east. By 1902 the complex had been renamed the New Barracks, with two additional buildings to the south and, to the north-west, two military cemeteries. The site sat only about 200 metres from another military barracks to the west, making this a corner of north Cork that was, for a period, heavily militarised. The surviving officer's mess is worth examining closely: rusticated limestone construction, a twelve-bay north elevation with a central open pediment, and ornate brick-dressed round-headed windows with a decorative cornice, all pointing to a mid-to-late nineteenth-century date for the building as it now appears. The entrance archway on the east side survives, as do several ordnance stones, small boundary markers used to define the limits of military land.