The Castle is renowned for its links with Grace O`Malley, a pirate sea Queen who inhabited the castle in the latter part of the 16th Century.
The castle is four floors high with a small rectangular corner turret rising above the parapet.
The principal apartment was in the top floor where there is a fireplace.
The building was restored by the diplomat Sir Owen O'Malley, a direct descendant of Grace O'Malley.
The castle is signposted (as Carrickahowley) just off the N59 between Newport and Mulranny.