‘Coosan Castle’

Site of 16th century O’Brien castle probably a tower house that was visited in 1979 and described as following: ‘Nothing is now visible of any structure or enclosure. The nearby field boundaries are modern field fences’ (SMR file). A dry stone wall forms the W boundary of the field in which the castle was situated. A new school has been built in the adjoining field to the W of the castle site. On the 1837 ed. OS 6-inch map Coosan Castle is depicted as a rectangular building aligned E-W with field boundaries running off the SE and SW angles of the castle. No castle building is depicted at this location on the revised 1876 ed. OS 6-inch map or on the 1910 ed. OS 25-inch map. Coosan Castle was the residence of Donell Reogh O’Brian who died on the 6th of February 1599/1600 (Nicholls 1970, 114). During his lifetime Donell O’Brian along with his younger brother Many O’Brian of Cornamagh helped ‘his said brother to build and make upp a castle’ at Coosan (Nicholls 1970, 114). Compiled by: Caimin O’Brien Date of upload: 08 May 2014

Coosan Castle was likely built by the O’Brien family in the 16th century. It is remembered as an example of early Irish tower house architecture, though its exact historical significance remains unclear due to the lack of visible remains.