The ground-plan of the cathedral consists of a nave with aisles terminated at the east end by three semicircular apses. There are a sacristy on the north of the choir-aisle, and a tower to the north of this. There are two doorways on the south side, three at the west end, and one on the north side. A grand crypt with arches on slender shafts occupies the whole space under the eastern part of the church. The access to the choir from the nave is by stairs against the aisle walls in the same position as at San Zenone, Verona. Here the stairs and their handrails are not later than the thirteenth century, and the choir is divided from the aisles by screens of the same age; solid below, and with a continuous cornice carried on coupled shafts above. The cathedral is said to have been founded in 1099, but an inscription on the south wall gives the date of the consecration of the building by Pope Lucius III. in July 1184. I believe that the former date represents the age of the plan, and of most of the interior columns and arches still remaining, but that before the later date the whole exterior of the cathedral had been modified, and the groining added inside. The work of both periods is extremely good and characteristic. The columns of the nave are alternately great piers and smaller circular columns of red marble. The great piers carry cross arches between the groining bays, and each of these in the nave is equal to two of those in the aisles. The capitals here are very close imitations of Classical work, with the abaci frequently concave on plan. The main arches and the triforium openings of three lights above them are seen both in the nave and aisle, the vaulting of the latter being unusually raised. There is also a plain clerestory, and the vaults are now everywhere quadripartite. The outside elevation of the side walls is very interesting. Here we seem to have the old aisle wall with its eaves-arcade added to and raised in the twelfth century, and adorned with a fine deep arcade in each bay, inclosed under round arches, which are carried on half columns in front of the buttresses or pilasters. These arches shew exactly what the original intention was at Ferrara, where it will be recollected they still in part remain. Certainly they would have made the side walls very rich in their effect, even if there had not also been two porches, a projecting pulpit, and various bas-reliefs inserted in them.