The Cathedral is attributed to the eleventh and twelfth centuries, and as it now stands consists of a large nave, without aisles, which were swept away for purposes of roof construction, as at Angers and in Notre-Dame-de-la-Coûture at Le Mans. According to Mr. Bond, an early tower was built in 550, which was noticed by Fortunatus. In plan the building shows the influence of the well-known church of the Cordeliers at Toulouse. "Its western portion is a vast nave without aisles, sixty feet wide internally and nearly two hundred feet in length. Its foundations show that, like that at Angoulême, it was originally roofed by three great domes; but being rebuilt in the thirteenth century, it is now covered by an intersecting vault ... and an immense array of flying buttresses to support its thrust, all which might have been dispensed with had the architects retained the original simple and more beautiful form of roof."
Within easy distance of Bordeaux is Libourne, a little town upon the Dordogne, which, though now overshadowed by the great port of the Garonne, was in the Middle Ages of almost equal importance in the wine-growing country, and had a special interest as being one of the _villes bastides_ found in several places in the south of France, especially in Guyenne. These really owe their origin to England, for they were founded by Edward I. during his French wars as refuges for those unable to take an active part in the struggle.
Mr. Barker, in his "Two Summers in Guyenne," gives a very interesting description of these towns, noticing particularly the straight lines of their streets. "In contrast to the typical mediæval town that grew up slowly around some abbey or at the foot of some strong castle that protected it, and in the building of which, if any method was observed, it was that of making the streets as crooked as possible, to assist the defenders in stopping the inward rush of an enemy, the streets of the _bastide_ were all drawn at right angles to each other." The _bastides_ were built merely for shelter, not, as was the case with other towns, for defence as well, though in the lawless days of the thirteenth century it was sometimes necessary even here to put up a wall, palisade and moat. Libourne has a remnant of such fortification in a quaint old round Tour de l'Horloge with machicolations and a pointed roof. The term _bastide_ was also applied to a single work of defence which, although isolated, formed part of a continuous system of fortification. A single house outside the walls of a town was also called a _bastide_.