Carrigrohane castle was originally constructed by the McCarthys. It was the headquarters of the Barretts from circa 1363 and the castle remained the Barrett headquarters from approximately 1370 to 1436, when the castle was sold to the Fitzgerald Earl of Desmond. Upon being evicted, the Barretts purchased Ballincollig in 1468 and established their stronghold there.The original castle on the site was already in ruins by the late 16th century, and soon afterwards a fortified house was built next to it, incorporating part of the older structure.
Local residents believe that a cave at the base of the rock on which the ruin stands was used to communicate with the Ovens caverns, 6.4 km away. Situated at a river bend above the castle site is a deep pool, called Hell's-Hole, overhung by limestone cliffs, which is imagined to be haunted by a "monstrous biped, having a mane like a horse, and a body like an eel".
The castle became dilapidated in 1641 during the Irish Confederate Wars but was later repaired. Circa 1665, the castle was reportedly the residence of the raparee/ highwayman Captain Cape. 'Researches in the South of Ireland' by Thomas Crofton Croker in 1824 described how Cape, "with a gang of desperate associates, plundered travellers and laid the neighbouring country under contribution in the most daring manner".
Carrigrohane was a fortified house that came into the possession of the Hoare family through marriage with a member of the Baker family in the 1770s. In 1786 Wilson refers to Carrigrohan as the seat of Mr Colthurst. It was described as consisting of "two structures differentiated by age, altitude, bulk, and architecture - the larger and older of which is oblong, and three-storied".
The fortified house had too fallen into dereliction by the early 19th century. Windele noted in the early 1840s that only its walls remained. It was taken over in the 1830s by Augustus Robert McSweeny / McSwiney a corn merchant, who also leased the flour mills nearby. The reconstruction was overseen by the architects Deane and Woodward from 1849-50.
At the time of Griffith's Valuation, Jane McSweeny was resident. The Castle later reverted back to the Hoare family who owned it until the 1940s.
The Hoare family are mentioned by the Irish Tourist Association survey as resident there in the 1940s. In 1976, it was bought by the well-respected local businessman and property developer, Leo O'Brien and the castle was occupied by the O'Brien family for 40 years up until 2015. It was sold in 2017.