The structure measures 7.4 metres east to west and 5.6 metres north to south, featuring a vaulted passage that runs north to south through its centre. Though time has taken its toll on much of the vaulting, visitors can still make out the round arch that frames the northern entrance to this 3.6-metre-wide passage.

The western side of the passage contains a flat-arched doorway leading to what would have served as a guard room, complete with its own north-south barrel vault. This chamber is lit by windows in both the north and south walls, allowing those on duty to maintain watch over approaches to the gateway. The defensive nature of the structure becomes even clearer when examining its vertical circulation; a narrow doorway, just 78 centimetres wide, pierces the south wall and opens onto a newel staircase that spirals up to the first floor.

The upper level reveals a more comfortable space that likely served both defensive and residential purposes. Large windows in the north and west walls would have provided ample light and views of the surrounding landscape, whilst a fireplace built into the east wall, flanked by two small windows, suggests this room offered some comfort to those stationed here. This combination of defensive features and liveable spaces reflects the dual nature of medieval gatehouses, which needed to control access whilst providing accommodation for guards and gatekeepers.