Black Castle was granted to John de Claville by Hugh de Lacy, the powerful Norman baron who governed Ireland for Henry II. The present castle was built by Sir Edward Bellingham in 1547 and fell to Cromwell's forces in 1650. The site was long held by the Kavanaghs and the Butlers and was also occupied by Sir Peter Carew and the Bagenals. All that remains today is the west half of a 14th Century round tower and part of the bawn.
It is accessible direct from the river towpath.