Baiano is a commune, population 4,743, in the Province of Avellino in the Italian region Campania, located in the Agro Nolano. It borders the co…Baiano is a commune, population 4,743, in the Province of Avellino in the Italian region Campania, located in the Agro Nolano. It borders the communes of Avella, Mugnano del Cardinale, Sirignano, Sperone and Visciano. The municipality of Baiano is a mountainous municipality in Irpinia and covers an area of about 12.25 km2 in the Partenio Regional Park.