Inside the crypt of the Royal Palace, in the Chapel Treasury, there are precious objects that recall the history of the church, such as furniture, furnishings, monstrances, liturgical vestments, codices, icons, reliquaries and relics, all dating back to Norman and Swabian times. Reading the 1309 inventory, a transcription of a 1277 Angevin document, we can see that part of the ancient core of the Treasury has unfortunately been lost.