the houses, the façades, had to line up. Also, there had to be a small space between the houses. The different housing lots were all alike, 8 m (26 ft) by 24 m (79 ft) being a common size. There were only a limited number of lots. This varied between ten and several thousand (3,000 in Grenade-sur-Garonne) Streets The streets were usually wide, so a chariot could pass through. They ran alongside the façades of the houses. Alleys run between streets, these are usually only wide. Sometimes, they are only wide. In a bastide there were usually between one and eight streets. City walls When bastides were founded, most had no city walls or fortifications because it was a peaceful time in history, and walls were prohibited by the Treaty of Paris (1229). Fortifications were added later and were paid for through a special tax or carried out through a law that required the people of the city to help build the walls. A good example is Libourne. Ten years after the city was founded, the people asked for money to build city walls. Once they had received the money, they spent it on making their city prettier, rather than building walls. At the beginning of the Hundred Years' War, many bastides that had no city walls were destroyed. Some of the others quickly built stone walls to protect the city. Structure and location Ease of tax collection was another reason for the grid layout, as the village was taxable module by module, and the organized central area. The bastides' forms resulted from "the friction engendered by interaction, expedience, pragmatism, legal compromise, and profit," Adrian Randolph observed in 1995. More rarely, such planned cities were developed according to a circular plan. Some bastides were not so geometrically planned: "The block geometry of the bastides was not a rigid framework into which a town was squeezed; it resembles more closely a net, thrown upon the site and adapting to its nuances," Randolph remarks. Most bastides were built in the Lot-et-Garonne, Dordogne, Gers and Haute-Garonne départements of France, because of the altitude and quality of the soil. Some were constructed in important defensive positions. The best-known today are probably Andorra la Vella and Carcassonne, but the most populated is Villeneuve-sur-Lot, the "new town on the River Lot". See also This heritage has been emphasized in the tourism in the southern regions. Ring