It was later encased in stone and saw modification and restoration in the 19th and late 20th centuries, though its medieval layout remains.
Cafodd ei orchuddio’n ddiweddarach â charreg a bu’n destun gwaith addasu ac adfer yn y 19eg ganrif a diwedd yr 20fed ganrif, er bod ei gynllun canoloesol yn parhau.