13th and 14th
century maps identify the town as “Balneoli” or “Bagnuolo”. In the Norman period it was in the hands of Beraldo, Count of Isernia, while in the
Swabian period it belonged to the Counts of Molise. The castle, of Longobard origin, is perched on a rocky spur with a commanding view of the Trigno river
valley, a strategic position halfway between two major sheep-tacks. The Normans modified the previous structures, raising well-set escarped walls: slightly
pronounced overhanging ones on three sides, while the front entrance wall is more prominent. The castle, four-sided, with buildings against the inner walls, has
suffered numerous modifications through the course of time and all signs of military installations have been erased. A loophole and some openings that appear to
have served as cannon ports still remain.