On the extreme tip of the Isle at the very end of the road, facing the full force of the Atlantic on a raised rock is Carrickagraghey Castle.
The Isle of Doagh was once an Island but now is connected to land by road. Its form now is essentially that of a peninsula (with in peninsula).
Another link in O’Doherty’s defensive network, it resembles both Inch and Burt in construction. Built before 1600 it was occupied by Phelemy Brasleigh O’Doherty.
Because of its seclusion it was chosen by Cahir O’Doherty to plan his revoly.
From the loops of the remarkably complete castle, Pollan Strand, the locationof a vicious and bloody battle for the lordship of Inishowen in the sixteenth century, is visible.
It is thought that the original castle complex was more expansive than today stretching to where more modern building has taken place.