The exterior of the Cathedral, imposing from a distance, is rather complicated in its unfinished compromise of detail. In the XV century, two towers were built which flank the western end as towers usually flank a facade; and this gives the church a foreshortened effect. Of real facade there is none, and the front wall which protects the choir is plainly temporary. In front of this wall there are portions of the unfinished nave, stones and other building materials, a scaffolding, and a board fence; and the only pleasure the traveller could find in this confusion was the fancy that he had discovered the old-time appearance of a Cathedral in the making. The apse is practically completed, and one has the curious sensation that it is a building without portals. Having no facade, it has none of the great front entrances common to the Gothic style; neither has it the usual lateral door. The choir is entered by the temporary doors of the pseudo-facade; the ambulatory is entered through the Cloister, or a pretty little Gothic door-way which if it were not the chief entrance of the church, would properly seem to have been built for the clergy rather than for the people who now use it. If these portals are strangely unimportant, their insignificance does not detract materially from the stateliness of the apse, which is created by its great height--one hundred and thirty feet in the interior measurement--and the magnificent flying-buttresses. These flying-buttresses give to the exterior its most curious and beautiful effect. They are a form of Gothic seldom attempted in the South, and exist here in a rather exceptional construction. Over the chapels which surround the apse rise a series of double-arched supports, the outer ones ending in little turrets with surmounting crenellations. On these supports, after a splendid outward sweep, rest the abutments of the flying arches. These have a fine sure grace and withal a lightness that relieves the heaviness imposed on the church by the towers and the immense strength of the body of the apse. They are the chief as well as the most salient glory of the exterior, and give to the Cathedral its peculiar individuality. [Illustration: "THESE FLYING-BUTTRESSES GIVE TO THE EXTERIOR ITS MOST CURIOUS AND BEAUTIFUL EFFECT."--NARBONNE.] Apart from its buttresses, Saint-Just has little decorative style. Its crenellations and turrets are military and forceful, not ornate. For the church had its defensive as truly as its religious purpose, and formerly was united on the North with the fortifications of the Palace, and contributed to the protection of its prelates as well as to their arch-episcopal prestige.