The oldest part of the building is the square keep, which still stands today. Openings were made for muskets. A second floor was added to the keep at a later date. The circular tower, which can be seen in a demolished state, was built separately from the keep and does not bond with it. A wall and doorway were built to support it. A number of lintels are still intact. Most of the present structure dates from the mid-1600s. It is built on a rocky promontory and sea-sand mortar was used. There is evidence of a window and door entrance. Stairs led to the second floor and holes in the wall show the position of the joists.

From the loops of the castle, Pollan Strand, the location of a vicious and bloody battle for the lordship of Inishowen in the 16th 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. Return to the main road, turning left for Carndonagh. Rashenny Stone Alignment is on the left in a field alongside the road overlooking Trawbreaga Bay.