The name Ballytarsna, meaning ‘town of the cross’ or ‘crossroads’, hints at the site’s long-standing importance as a meeting point. Built from roughly coursed limestone rubble with cut limestone quoins, the tower measures 10 metres north to south and 8.58 metres east to west, with walls 1.8 metres thick at ground level. Its defensive base-batter extends 3 metres high and terminates on either side of the main entrance, a pointed doorway on the western wall that leads visitors into a carefully designed defensive lobby complete with murder-hole and cross-loop.

The castle’s history is steeped in local lore and documented ownership. According to Lewis’s 1837 account, the structure was allegedly built by a member of the Hacket family, who met a grim end at the hands of one of Cromwell’s generals. Historical records confirm Piers Hacket held Ballytarsne in 1546, whilst Patrick Hackett was listed as proprietor in 1640. By the time of the Civil Survey (1654-6), the property comprised ‘one good Bawne & a Castle wanting repaire, with severall small Cottages’, suggesting the fortification had already seen better days following the tumultuous years of the Cromwellian conquest.

The interior architecture reveals the sophisticated planning typical of Irish tower houses, with each floor serving distinct purposes and accessed via mural stairs spiralling through the southwest angle. The ground floor chamber, now sporting a modern concrete floor, receives light through three partially reconstructed windows. As visitors ascend, they encounter increasingly refined spaces: the first floor with its pointed vault, the second floor featuring window seats carved from limestone, and the upper levels boasting elaborate two-light windows with cusped ogee heads. Particularly intriguing are the castle’s hidden features; a concealed oubliette beneath the fourth floor, accessed through a trapdoor in a mural passage, and various garderobes, wall cupboards, and defensive elements including gun-loops beneath window sills. The roofline retains its crow-step crenellations, bartizans at the northwest and southeast angles supported by pyramidal-chamfered corbels, and a turret at the northeast corner, all testament to both the castle’s defensive capabilities and the status of its builders.