As you approach this impressive eagle's nest, you are struck by the beauty and calm of the site. In the 11C, Sanche Ramirez, King of Aragon and Navarre, had this fortress built at 1,100 m altitude and installed a monastery here. Once you go through the wall with its round towers, you discover an immense panoramic view over the Ebre depression The massive keep, a fine vaulted staircase and the 12C Romanesque church are interesting.