Ballincollig Castle Ballincollig Castle is a Norman castle to the south of the town of Ballincollig , County Cork , Republic of Ireland built after the Norman invasion of Ireland . In its prime , the castle was inhabited by the Barrett s , who had control of the local area . The castle still stands today , albeit heavily damaged . The original keep still remains , as does most of the curtain wall and two towers set therein . Features . There appear to be no early descriptions of the castle . Ballincollig Castle was constructed on a limestone summit , with a clear line of sight over the low land of the Maglin Valley . Beneath the castle there is a dark natural cavern which runs into the rock and around it the remains of a moat . Wall and Enclosure . The castle consisted of a large walled enclosure ( or bawn ) , with a tower or keep on one side of it and possibly a large hall through the middle . Most of the enclosing or outer wall remains . It is about 5 ft thick and 15 ft high . The space on top was defended by a parapet with flights of steps leading up at several points . There were two defensive towers on the wall , one at present in ruins in the south - east corner and the second on the south wall . The enclosure is between 70 – 100 feet across and is rocky and uneven . There appears to be evidence of a hall in the middle as one portion of the outer wall has the remains of a fireplace and chimney and a window of two lights . It is suggested that the towers on the outer wall and the hall are of 15th century making and were probably built after the sale of the castle to the Barretts . The Keep . On the other hand , the main tower or keep is of the 13th century and was used by Coll . The keep was repaired by the Wyse family in 1857 and on the east wall a shield has been inserted bearing the monogram W with the date 1857 beneath it . The keep is 45 to 50 ft in height . The ground floor is vaulted and originally had no entrance to it except by a trap door from above , so it was probably a prison . The room on the first floor had a path up to it , carried on arches . It is about 7 . 5 ft by 9 ft . A very narrow staircase leads to other stories , all of which have stone floors on solid arches . To support them the two walls on which they rest are thicker than the others . The second story has seats in the lambs of the loopholes , a drain from a lavatory and a small square cupboard in the wall over it . The upper floor of chief chamber seems to have had windows added on all sides in the middle of the 19th century . However , there are loopholes in other parts of the walls of the keep . The lack of windows and a fireplace and the fact that the small rooms occupied all the internal space between the walls suggests that the building was more of a keep for last defence than a regular living quarters . History . The Conquest of Ireland . The Barretts travelled from Normandy with William the Conqueror and helped him to conquer England in 1066 . They subsequently received grants of land in Pembrokeshire , Wales . Some of these Barretts travelled with the Normans when they came to conquer Ireland in 1169 . When Henry II parcelled out the spoils of conquest in Ireland he gave the Kingdom of Cork , stretching from Lismore , County Waterford to County Kerry , to Milo de Cogan and Robert Fitzstephen . De Cogan received land west and south of the city and the family built a number of castles on their lands including one at Carrigrohane . The Barretts were underlords of the de Cogans . They rose in influence through service to various kings . The Barretts travelled to conquer Connacht in 1235 under John de Cogan who led the Munster contingent . Because of this they seem to have become tenants of Carrigrohane under John Barrett for King Edward II in wars in Scotland , the king pardoned Crown debts and rents chargeable on his heir , William Barrett . The Barretts . During the 15th century the Barretts seem to have settled down to a reasonably peaceful existence . They were now underlords of the McCarthys to whom they paid rent of £11 a year from 1420 and later the Earls of Desmond to whom they paid 12 marks yearly after 1425 , when the Desmond were granted de Cogan lands . After the middle of that century they purchased Ballincollig Castle . In the Carew Calendar , 28 November 1611 , Sir Dominic Sarsfield wrote to Lord Carew , " Ballincollig is entailed and was purchased in the 8th year of Edward 4 ( 1468 – 9 ) from Robert Coil , a knight . Deed of entail in my own lands " . This was to become the principal Barrett stronghold until the early 17th century when Castlemore Barretts seem to have had ( Mourne Abbey ) , Garrycloyne ( both in the north of the Barony ) , Castleinch , Ballincollig and Cloghan McUllick about 2 – 3 miles south or south - west of Ballincollig . The exact location of the latter is not certain . Some historians suggest the present townland of Grange but there is some doubt about this . However , the Barretts also controlled Carrigrohane for some time . In the 1590s a dispute arose . In July 1591 Andrew Barrett and sixty others assaulted Ballincollig Castle and dispossessed Edmund Barrett , " with swords , guns , great sledges or hammers , skenes , stones and staves " . Three years later Edmund got a decree of £100 against Sir Fineen O ' Driscoll , Sheriff of Cork , for refusing to execute a writ dispossessing Andrew Barrett and others who had seized the castle . In the following year , 1595 , Edmund took his cousin to court . A fine of £20 was imposed on Andrew and lesser fines on two others and they were jailed . Castle Lost . However , early in the 17th century , the Barretts lost Ballincollig Castle . The family were driven to borrowing money to pay for court fines and dowries . They had to obtain a mortgage on the castle and lands in 1618 from the Coppingers of Cork who were moneylenders . " William Barrett of Ballincollig in the County of Cork , gent , … in consideration of £240 paid by Edmond Coppinger Fitzrobert of Corke , gent , the said William Barrett granted to the said Edmond Coppinger , his heirs and assigns for ever all that and those the castles , bawnes , towns , villages , hamlets , lands , tenements and hereditaments of and in Ballincolly … ” . This mortgage was transferred to Walter Coppinger , Cloghane ( near Skibbereen ) and in 1630 for the payment of £790 to the Barretts , Coppinger came into full possession of the castle and lands . The castle featured briefly in later history . In 1644 it was taken by Cromwell ' s forces and around 1689 it was garrisoned for James 2 . But after 1690 it was unused and it fell into disrepair . Today . Today the castle is in private ownership .