The aisles have groin vaults over each bay. The vaults work as internal buttresses for the lower part of the nave walls. Above the aisles are the galleries. Now used only for storage, in the Middle Ages the galleries contained extra chapels. They also helped stabilise the nave walls, because the timbers of the gallery roofs buttressed the nave wall below the clerestory.
'The door jambs have the signs of the zodiac ...'
The south aisle has two doors. The one towards the west end is called the Prior's Door. If we go through it, we will be in the remains of the cloister that connected the dormitory and refectory to the church.
The Prior’s Door has a tympanum showing Christ in Majesty with two angels, reminding the viewer of the Last Judgement. The door jambs have the signs of the zodiac, which symbolised the yearly cycle of work and prayer.
The Monks’ Door at the east end of the aisle has swirly foliage patterns in the carving. These are similar to the patterns in the 12th-century painting on a nearby section of the south aisle vault.
The monks didn’t do stone carving or wall-painting (that was done by professional craftsmen, just like today’s builders). But, the similarity between these motifs and a manuscript that was made by the monks suggests that the monks provided the patterns for the craftsmen to work from.