The patron saint of Ariano Irpino is Saint Otto, celebrated on 23 March.
Between the 17th and 19th centuries, five fairs were held in the town, linked to various religious occasions: one of these, the patronal fair of Saint Otto, had even older origins than the others and enjoyed special privileges. This schedule soon proved inadequate, partly because in some years the coincidence with Holy Week prevented the patronal fair from being held, and it was later permanently suppressed. The town today hosts cultural events such as the Ariano International Film Festival, in July and August, and the Ariano Folk Festival, a showcase of ethnic music in August. Among the town's places of interest are the Cathedral of Santa Maria Assunta and the Castle of Ariano.
