Located in the west of Ireland, with twenty three parishes in Counties Roscommon, Mayo and Sligo. Suffragan of of the archdiocese of Tuam. The cathdral is located in Ballaghaderreen and is dedicated to The Annunciation and Saint Nathy. Saint Finian was an early missionary. The long list of its bishops includes Saint Nathy, reputed first bishop (c.560), and Eugene O'Hart, present at the Council of Trent. See also