Richard the Lionheart signed a treaty of alliance with Alphonse of Aragon, strengthening his hold over all of Aquitaine. I hadn't realized until I began reading about the area that Richard spent most all his life here in France and actually couldn't speak English...he spoke the ancient langue d'oc and is reported to have disliked England as it was 'cold and rainy.'
This open area inside the thick walls was designed to hold up to 300 people in times of siege. Various partially restored rooms open into it. In one area the wall has been opened up to allow a view of a multiple story cylindrical room built inside the wall. At the bottom is the dungeon where prisoners including some Knights Templar were held.
There's more to see, so come back!