The work for Cathedral of St. Mary of the Assumption started in 1175 on the site of earlier church destroyed in 1155 by Frederick Barbarossa, was then consecrated by Pope Innocent III in 1198, and finally completed in 1227. Also the church of the eleventh century, destroyed by the emperor, was biult on the ruins of a former church built in the eighth or ninth century, dedicated to St. Primiano, which has been preserved in the crypt of the present Chapel of the Relics. The façade is the result of an enlargement of the previous one, which occurred around 1200. Rosettes were then added to the exterior of the second order and three rosettes, niches and a mosaic of the third order. The latter, in paerticolare, is "Blessing Christ enthroned between the Virgin and St. John the Evangelist. " The central rosette, which belongs to the twelfth century, is one of the richest in Umbria. It the corners it contains the symbols of the four Evangelists. The porch was added in 1491-1504 and is the work of Ambrogio di Antonio barocci from Milan and Pippo di Antonio from Florence, with five arches. At his side stands the massive tower of the twelfth century, which was also used for defense purposes. The belfry was added in 1512-15 by Cola di Caprarola. Beside the main door is walled up the entrance of the cathedral of the ninth century, St. Primiano.