The Castle was the scene of fighting with the Earl of Essex in 1599. In 1645 it was captured by Lord Castlehaven and was assaulted but not taken by Cromwell in 1650. Conna Castle was burned in 1653, killing three daughters of the occupant and afterwards passed to the Duke of Devonshire's family. It is a five storey square tower house approximately 85 feet tall with only one ceiling still intact.
The Castle is situated within a public park in the village of Conna. The Castle is not open to visitors but the park is freely accessible.