This masonry structure measures 3.8 metres north to south and just over 3 metres east to west, featuring an entrance passage nearly two metres wide. The gateway’s defensive capabilities are evident in its construction; each internal pier contains two draw-bar sockets that would have secured heavy wooden bars across the entrance, whilst the remnants of a spiral staircase in the southern pier suggest there was once an upper level, likely used as a guard chamber or lookout point.

The gatehouse displays several architectural features typical of medieval Irish fortifications. The eastern face of each pier sits atop a coped plinth rising 1.5 metres from ground level, with a decorative string course running horizontally above. The stonework also preserves the springing points where an arch once spanned the entrance, creating an imposing facade for those approaching from the east. The structure’s placement is particularly strategic, as its passage aligns directly with the entrance through the eastern range of the college, providing controlled access straight into the cloister at the heart of the religious complex.

Whilst the gatehouse clearly served the college, it may have had an additional purpose connected to the nearby tower house. Some evidence suggests it could have functioned as the entrance to a small bawn, a fortified enclosure that would have protected livestock and provided refuge during raids. This dual role would have been common in medieval Ireland, where religious sites needed both ceremonial entrances for daily use and defensive structures to protect their communities and wealth during turbulent times.