The western entrance is on the current Via Matteo Bonello, and has the appearance set in the 14th and 15th centuries. It is flanked by two towers and has a Gothic portal surmounted by a niche with a precious 15th-century Madonna. Two lintelled ogival arcades, stepping over the street, connect the western façade to the bell tower, which is annexed to the Archbishops Palace (now Museo Diocesano). This has a squared appearance adorned in the upper part by a fine crown of smaller belfries and small arcades.