From 1190 to 1215, Philippe Auguste had a wall built around Paris. On the western side, he built a solid square fortress, the Louvre Castle. Its 32-metre high keep served as the monarchy’s vault as well as a prison. During the Middle Ages, the expansion of Paris brought the castle inside the walls. Charles V transformed the garrison castle into a leisure residence: he added windows and created gardens. Under François I, the Louvre was modernised into a Renaissance palace, and the keep was demolished. The present Cour Carrée is a fourfold enlargement of the former medieval keep quadrangle.