Located below E wing of St Mary's College and Cloister Hall. Of barrel vault construction. Probably three in line beneath the house and outbuilding, two parallel behind the house, and an uncertain configuration under raised platform extending towards the river. The latter undercrofts are not accesible.
(Source CADW listed buildings database)
J Hill 22.10.2003

Cloister Hall = Nprn21797.

Part of:
St Mary's College (Nprn305386).