In the 15th century, the castle was modified to keep up with developments in artillery design. It was decommissioned from a military post to become a comfortable residence for Jeanne of Laval-Châtillon and her son Anne de Montmorency. At the same time, many half-timbered houses and private mansions were built inside the city. These medieval districts are characterized by their sturdy frame construction and their sinuous and dark streets, as well as by a network of lanes. From a defense perspective, these narrow streets were a confusing obstacle to taking the city. The frontages of the houses are made either of half-timbering or stone. The corbellings (projection of the higher floors over the street) helped save space. They shielded pedestrians from bad weather, and they channeled rainwater into the central gutters, helping preserve the wooden facades.