Intimately associated with the history of the palace of the Popes of Avignon is that of the unparalleled circuit of walls and towers which defended the city from the scourge of organized robber bands during the fourteenth century. The earliest quadrilateral fortifications embraced a relatively small area consisting of the Rocher des Doms and the parishes of St. Agricol, St. Didier, and St. Pierre; these walls, demolished and rebuilt on a more extensive scale in the twelfth century, embraced an area easily traceable on the modern map, from the Porte du Rhone, round the Rues du Limas, Joseph Vernet, des Lices, Philonarde, Campane, Trois Colombes, to the Rocher. It was these fortifications that the Cardinal St. Angelo forced the citizens to raze in 1227. Until the acquisition of Avignon by Clement VI., the city was an open one and only defended by a double fosse. The origin of the papal walls has already been traced, and their subsequent fate may now be briefly given. The assaults of the Rhone proved more destructive than human artillery. The walls and towers having been hastily raised, towers fell by reason of bad foundation, and the upkeep of the fortifications was a continual drain on papal and communal finances. In 1362 an irresistible flood of waters overthrew the Fortes St. Michel and Limbert, and large breaches were often made by these recurring inundations. Moreover, the expansion of the city of old and the need of access to the suburbs involved frequent displacement and opening of new gates. In 1482 the whole system of the defensive works was modified to meet the new situation caused by the introduction of gunpowder. The gates most exposed to attack were further defended by outworks, that of St. Lazare having been fortified during the rule of Giuliano della Rovere by the addition of a powerful bastide, with three round towers, a drawbridge, a new fosse which communicated with the great fosse before the main walls. Other modifications took place during the Huguenot wars. Notwithstanding many repairs during the intervening centuries, the fortifications had, under the second Empire, suffered sad degradation, and at length Viollet-le-Duc was entrusted with their restoration. The famous architect set to work on their southern side and had completed about one-third of the restoration when the disastrous issue of the Franco-Prussian war arrested all further progress until the Third Republic feebly resumed the task. The walls along the Rhone, especially useful in time of flood, were backed with stone, their battlements and machicoulis renewed. The visitor, however, will need no reminder that the present passive aspect of the ramparts conveys but a faint impression of their former state, when a broad and deep fosse, seven feet by twelve, washed their bases, above which they raised their once impregnable curtains full thirty feet.