This four-storey limestone tower, built from coursed blocks with carefully dressed quoins and window surrounds, represents all that remains of what was once a grand residence. Its rectangular form rises imposingly from the ground, complete with a stair turret tucked into the northwest corner and a distinctive base batter visible along the eastern wall.

The building has undergone considerable changes since its original construction, particularly during the 19th and 20th centuries. The ground floor, originally vaulted, now serves as a chapel following the insertion of Gothic windows; a transformation that speaks to the building's evolving religious use. A spiral staircase within the turret, accessed from the south side and lit by narrow slit windows, leads visitors to the upper floors. The first floor features a later fireplace built into the north wall, whilst round-headed windows pierce all four walls, with the western opening cleverly doubling as a doorway.

Dating the gatehouse has proved somewhat contentious amongst historians. Whilst tooling marks on the stonework suggest 16th-century craftsmanship, these may simply indicate later modifications to an earlier structure. The third floor's vaulted ceiling, running east to west, appears to be a modern addition. During restoration work, Sir John Lentaigne discovered a carved stone head reused within the stair walls; a tantalising fragment that hints at the building's complex history of construction, destruction, and renewal through the centuries.