Though partially cloaked in ivy and missing some of its corner stones, this late medieval stronghold retains its commanding presence over the surrounding landscape. Built sometime after the 1570s as the chief stronghold of the O’Learys, with some sources suggesting it served as the tánaiste’s (heir apparent’s) tower house, the castle saw dramatic action in 1602 when it was attacked and captured by O Sullivan Bear during the turbulent period of clan warfare that marked the end of Gaelic Ireland.

The tower’s defensive sophistication becomes apparent upon closer inspection, particularly in its distinctive triangular spur projecting from the southeast corner; a feature it shares with the tower house at Mashanaglass. Entry through the eastern wall leads into a cleverly designed lobby covered by a murder hole, from which defenders could rain down projectiles on unwelcome visitors. The interior reveals a complex arrangement of chambers connected by a spiral staircase in the northeast corner, which winds its way up to the third floor. Each level served different purposes: the ground floor, later repurposed as a cowhouse and granary, contains the main chamber with its defensive windows; whilst the upper floors housed living quarters complete with fireplaces, garderobes, and even a corner bartizan supported by tapering lintels and equipped with five gun loops for defensive fire.

Perhaps most intriguing are the castle’s military innovations, including the wedge-shaped chamber within the triangular spur fitted with gun loops that provided covering fire along the tower’s external walls, and the murder hole system that protected the entrance. The second floor features a pointed wicker-centred vault running east to west, whilst the third floor once opened onto battlements that have since been removed. Time and weather have taken their toll; notably, the western gable collapsed in a gale sometime before 1914, causing considerable interior damage. Despite these losses, Carrignacurra Castle remains an impressive example of late medieval Irish tower house architecture, embodying both the defensive necessities and domestic requirements of Gaelic lordship in its twilight years.