The rectangular main block, measuring approximately 12 metres north to south and 6.6 metres east to west, features distinctive square towers at each corner; a design that closely mirrors the nearby Monkstown Castle. Though time and conflict have taken their toll, with the western wall and portions of the northwest and southwest towers having collapsed, the remaining walls still rise to their full original height, complete with gables crowning each elevation and decorative string courses marking the division between floor levels.

The castle’s defensive capabilities are evident in its numerous gun loops, strategically positioned at ground level throughout the corner towers to cover multiple angles, with additional loops set beneath window openings. Entry to the main block was through a central doorway in the eastern wall, topped by an impressive elliptical arch cut from stone in two orders, though the northern jamb has since disappeared. The windows, most divided by mullions, vary in size with the grandest at first-floor level featuring two mullions and a transom. Many retain their external hood mouldings with stepped terminals, whilst the original wooden lintels survive in several embrasures, some bearing scorch marks that support the tradition that the castle was burnt by its own owners around 1643.

Each corner tower contained a single room per floor, accessed from the main block through lintelled doorways. Whilst no fireplaces remain in the central structure, the towers preserve several examples, including one in the southeast tower at second-floor level with a particularly fine elliptical arch cut into the lintel’s underside. According to an early 19th-century depiction by antiquarian Daniel Grose, the castle once stood largely intact, and historical accounts describe ornate cornices featuring carved figures depicting scriptural subjects and hunting scenes. Today, the structure faces significant conservation challenges, with major vertical cracks visible along the centre of the southeast tower’s southern wall and on both the eastern face of the southeast tower and southern face of the northeast tower.