The monastic buildings are now lost, and the exterior of the Priory Church can only be viewed from the north.
The North Transept and its Chapels have been ruined since 1800, but their ground plan can be easily seen. The chapels were barrel-vaulted, matching the western bays of the presbytery.
The chevron decoration on the entrance arch to the inner chapel ends with a dragon’s head similar to those found at Llandaff Cathedral.
The central Tower is fairly low for such a building. The battlements and arrow loops were added at the same time as the fortification around the monastic enclosure was built in 1300.
The monastic enclosure measured 190 by 130 metres, bounded by the Precinct Walls. The east wall is the simplest and unfortified, probably dating from the foundation of the Priory. The lower parts of the Gatehouses also date from this time, and enlarged in 1300, when the Towers were built, and the other walls heightened and embattled.