What survives today is primarily the western angle of the castle, rising about 8 metres to what was once wall-walk level, marked by a string course and five corbels that supported an angle machicolation. Built from coursed rubble with alternating cut stone quoins, the structure shows clear evidence of having been a substantial four-storey tower house, with wooden floors supported on beams whose holes are still visible in the surviving southwest wall.

The castle’s connection to the Dillons began in 1307 when King Edward II granted Sir Henry Dillon of Drumraney custody of the manor of Kilkenny West, which had been forfeited by Hugh de Lacie. The family’s influence grew over the centuries; by 1604, Theobald Dillon of Costello-Gallen was granted the right to hold a weekly Monday market at Kilkenny West along with two annual fairs. The 1659 Down Survey map depicts the castle as a tower house and records that the lands belonged to James Dillon, Earl of Roscommon, noting the presence of ‘a Castle with some Houses and Cabbins’ in the area.

Archaeological evidence suggests the castle remained relatively intact until sometime between 1837 and 1910, when most of its walls either collapsed or were deliberately dismantled, leaving only the northwest angle standing. Today, visitors can still make out architectural details including the remains of flat-headed windows with hood mouldings at various floor levels, stone corbels that once supported the first floor’s wooden beams, and grass-covered wall footings that trace the outline of the original structure. The castle sits in a landscape rich with medieval heritage, including a holy well 330 metres to the northeast, a church and graveyard 100 metres east, and an abbey 180 metres to the south-southeast.