The church of the old Benedictine monastery of San Pedro el Viejo is one of the essential monuments of the city of Huesca and of the Aragonese Romanesque. It is a beautiful building that within its walls the magic of the Romanesque from the beginning of the 12th century mural paintings from the 13th century and the jewel, the Romanesque cloister with thirty-eight historiated capitals, eighteen of them original.

Within this courtyard is the Royal Pantheon of the Kingdom of Aragon, with the tombs of two distinguished kings : Alfonso I the Battler, leader and conqueror of Zaragoza in 1118, and Ramiro II the Monk, protagonist of the aforementioned legend of the "The bell of Huesca".