BALLYHAUNIS, a market-town, in the parish of ANNAGH, barony of COSTELLO, county of MAYO., and province of CONNAUGHT, 9 miles (W. by N.) from Castlerea, and 97½ miles (W. by N.) from Dublin, on the road from Castlerea to Castlebar: the population is returned with the parish, A monastery was founded here for friars of the order of St. Augustine, and largely endowed by the family of Nangle, who afterwards took the name of Costello: it subsisted till the reign of Jas. I., and at the commencement of the insurrection in 1641 was restored by some friars of the same order. The remains of the ancient buildings consist only of the walls of a church, with two small wings connected with it by arches; on the site of the conventual buildings a modern house has been erected, which is at present occupied by Augustinian friars. The market is on Tuesday; and fairs are held on June 1st, July 2nd, September 22nd, and October 29th, chiefly for horses and cattle. The town contains a constabulary police station, and has a penny post to Clare and Frenchpark.- See ANNAGH.