Very little remains of Kit's Castle and these ruins can be seen on the hill above St. Catherine's Holy Well, Killybegs.
There is nothing to visit but you can view the ruins from the top of the path to the Holy Well.
Kit's Castle from the carpark
From Killybegs.ie:
"Kit’s Castle The Lost Fortress of Killybegs
Set just above the harbour within the St. Catherine’s Heritage Zone, Kit’s Castle dates back to 1355, when it was built as the residence of Bishop Pádraig Mac Maonghaill, who served the diocese of Killybegs until his death in 1367. Once a proud three-storey stone structure with its entrance facing west, the castle stood as a powerful symbol of ecclesiastical authority and local resilience.
One of the most notable figures to reside at Kit’s Castle was Bishop Dónal Mag Congail (anglicised as Donald McGonagle), who passed away in 1589. He was among only three Irish representatives to attend the final sessions of the historic Council of Trent, a major event in the Counter-Reformation.
The last known resident was Bishop Niall Ó Baoighill (Niall O’Boyle), a fierce opponent of the British invasion during the turbulent years leading up to and following the Battle of Kinsale in 1601. Following the Irish defeat, he fled the castle and died in 1611. The building has stood empty ever since and gradually fell into ruin.
Today, only a fragment of the northwest wall remains visible, largely overgrown by vegetation—a quiet but powerful reminder of Killybegs’ medieval legacy."
From duchas.ie (written in the 1930's):
"There are many old castles in different parts of Ireland, every one of these castles has some history attached to it. One of these is in Killybegs it is situated on top of a hill overlooking the village which was once described as Ireland's most beautiful village.
We do not know when the castle was built as there is no person in the locality who can recall the time when it was being occupied, but this story has been told to them by their ancestors.
There was once a bishop named Mc Gonigal living in Killybegs. He lived in the castle and only when it was a case of necessity he never left it. When he died he left the castle for a monks residence. For many years the monks lived happily in it, until at last, owing to the constant fall of stones they had to leave it before the walls fell in. It is believed that the day following their departure from the castle the roof and three walls fell in, leaving only one wall remaining. Bishop Mc Gonigal was buried in the old grave-yard which is only a short walk from the ruins.” COLLECTOR - Philomena Parris Gender - Female Address - Killybegs, Co. Donegal INFORMANT - Mrs Hannah O Boyle Gender - Female Age - 86 Address - Killybegs, Co. Donegal
DISABLED ACCESS The path to St. Catherine's Holy Well is smooth however it is quite steep (see photo below).