Various derivations are given of the old name Macromp. Some authorities state that it signifies the “Plain of Crom,” the supreme deity of the ancient inhabitants of Ireland. Smith says the name came from a crooked oak under which travellers used to pass, but it seems more probable that it simply meant “a crooked plain,” and referred to the undulating country round. In Smith’s History of Cork he describes the building as consisting of two square towers about 60 feet high connected by a large modern building. Windele, however, says that the present residence is a huge square mass of masonry which formed the keep of the original castle. It has a handsome gallery and other good apartments, and is now covered with ivy. At the beginning of the last century Gothic windows were introduced and part of it weather-slated, which, being entirely out of keeping with the style of architecture, has not added to its picturesqueness. It occupies a slight rise on the east bank of the Sullane River, which flows through the demesne. The gardens lie to the south. The castle appears to have been erected in the twelfth century, and its building has been variously attributed to the Carews and Daltons, while its Irish name of Caislean-i-Fhlionn, signifying “O’Flyn’s Castle,” seems to indicate that it owes its origin to this family, who formerly owned territory in Muskerry and Carberry. It afterwards came into the possession of the MacCarthys, and Tiege MacCarty, father of the famous Lord Muskerry, died in the castle in 1565, having restored and enlarged it. In 1602 its owner, Cormac MacDermot Carthy, Lord Muskerry, was suspected of hostile intrigues and imprisoned in Cork, while Captain Flower and then Sir Charles Wilmot were sent to lay siege to the castle. Lord Muskerry, however, escaped, and the Lord President fearing he might cut off Sir Charles’s retreat, ordered him to return to Cork. The night before the intended march the garrison killed a pig, but water being too scarce to scald it they decided to singe it instead with fern and straw. This they did in the castle bawn, but some sparks lighting on the thatched roof of a cabin flamed up and set fire to some tallow through one of the windows of the castle. The flames quickly spread through the building and the garrison was obliged to take speedy refuge in the bawn. From thence they made a sally to the woods, about fifty being slain in their attempt to escape. The besiegers entered the castle and extinguished the fire. After making some necessary repairs Sir Charles left a garrison there and marched to Cork. Upon the breaking out of the rebellion of 1641 it was again in Lord Muskerry’s possession, and when the Papal Nunzio landed in the south of Ireland he visited many places and amongst them Macroom Castle. He was received at the great gate of the fortress by Lady Helena Butler, sister of Lord Ormond, and the wife of Donough, Lord Muskerry. The Nunzio stayed at Macroom for four days.