The church is one of the very few in the department with side aisles to the nave. Indeed, the form affected throughout southern Languedoc is a vast nave without pillars, and chapels between the buttresses. This church was begun in 1275 and ended in 1313. It has a seven-sided apse. Over the west window is a gallery with machicolations, so that it could be used as a fortress, and melted lead or boiling pitch could be thrown down on besiegers. Narrow, steep, and dirty streets climb the hillside to the castle, now enclosed within the walls of a convent; little remains, however, but a keep of this once sumptuous seigneural residence of the barons of Clermont. Formerly it consisted of a semicircular ring of wall defended at intervals by seven round towers, and with an eighth on the side of the chord of the arc. The view from the height extends over the plain watered by the Hérault and the Lergue, that begins at the feet of the Lodève Mountains and extends to the low range of the Taillades de Gignac. From thirty to forty towns, villages, and hamlets dot this plain. [Illustration: S. GUILHEM-LE-DÉSERT] In 1209 Aimar Guilhem, seigneur of Clermont, was the ally of the unfortunate Raymond, Count of Toulouse, against whom Innocent III. hurled the thunders of excommunication because he would not butcher and burn his subjects, who had embraced the Albigensian heresy; and Aimar was accordingly involved in his sentence. Innocent called together the riff-raff of Europe to join in a crusade against Raymond, promising life eternal and absolution from all sins to those who would join in an indiscriminate slaughter of the Albigenses, and placed Simon de Montfort at the head of this horde of the Children of God, as they called themselves, who swept over the land committing indescribable horrors. After the massacre of the inhabitants of Béziers by the crusaders, Aimar retired to his castle and awaited events. His conduct may have been prudent, as he saved the town from sack and slaughter, but it was unworthy of him; as had he roused the country of Lodève, he would have menaced the rear of Simon de Montfort, and might have forced this commander of the soldiers of the Papacy to deal less cruelly with the seigneurs of Languedoc, whom he robbed of their domains with impunity.