The ensemble is an astonishing profusion of high and narrow windows, of which there are three rows: the clerestory, the triforium, and the aisles. Each window is divided into two by a column so fragile that it resembles a spider's thread. These windows peep forth from a forest of flying buttresses, and nowhere does the mixture of pinnacles and painted panes attain a more perfect eloquence than in the eastern extremity of the polygonal apse. The western and southern façades--the northern being replaced by the cloister--are alike in their general design, and are composed of three portals surmounted by a decidedly pointed arch which, in the case of the central portals, adorns a richly sculptured tympanum. The artistic merit of the statuary in the niches of both central portals is devoid of exceptional praise, that of the southern façade being perhaps of a better taste. As regards the stone pillar which divides the central door into two wings, that on the south represents Our Lady of the Blanca, and that on the west San Froilan, one of the early martyr bishops of Leon. Excepting the Renaissance impurities already referred to, each portal is surmounted by a row of five lancet windows, which give birth, as it were, to one immense window of delicate design. Penetrating into the interior of the building, preferably by the lateral doors of the western front, the tourist is overcome by a feeling of awe and amazement at the bold construction of aisles and nave, as slender as is the frost pattern on a spotless pane. The full value of the windows, which are gorgeous from the outside, is only obtained from the interior of the temple; those of the clerestory reach from the sharp ogival vaulting to the height of the triforium, which in its turn is backed by another row of painted windows; in the aisles, another series of panes rose in the sixteenth century from the very ground (!), though in recent times the bases have unluckily been blinded to about the height of a man. The pillars and columns are of the simplest and most sober construction, so simple that they do not draw the spectator's attention, but leave him to be impressed by the great height of nave and aisles as compared with their insignificant width, and above all by the profuse perforation of the walls by hundreds upon hundreds of windows. Unluckily, the original pattern of the painted glass does not exist but in an insignificant quantity: the northern window, the windows of the high altar, and those of the Chapel of St. James are about the only ones dating from the fifteenth century that are left standing to-day; they are easily recognizable by the rich, mellow tints unattained in modern stained glass.