Nothing remains of the church of the Anglo-Saxon monastery; nor is there
any Early Norman work, for, as we have seen, that church was allowed to
remain standing till the year 1107. But in the first half of the twelfth
century a Norman cathedral was commenced, and possibly finished, by
William Warelwast and his successors. That cathedral included both the
existing towers; it also included an aisled nave of the same dimensions
as the present one. The narrowed span of the westernmost arches of
the pier arcade is to be accounted for only on the supposition of the
existence, to the west, of the wall of a pre-existing west front (cf.
Lincoln nave). Also traces of Norman buttresses and pilasters, and one
base, have been found in the walls of the north and south aisles of the
nave. And traces of an apse have been found at the end of the third bay
of the choir. So it is plain that the twelfth-century cathedral had west
front, nave and aisles, transeptal towers, a choir of three bays, an
apse at the end of the choir, and probably some minor apses.