The remains of a building which is said to have served as a private chapel of St Patrick's Church. The building was orientated east-southeast to west-northwest and built of local, undressed stone with some red sandstone and quartz. It is situated 20 metres north of the Round Tower and internally it measured 8.8 metres by 4.1 metres, with wall surviving up to a maximum of 1.8 metres, being 0.7 metres thick.


It is doubtful that the building was designed as a chapel since the doorway is in the east end, and there are no features in the walls to show that there was any other entrance. A number of skeletons are said to have been found lying below the floor, in sand, but no stone grave or coffin appears to have been found.