Only a small tower was all that remained of this castle in 1608. In its heyday it was the seat of the O’Doherty generation that proliferated and expanded throughout Inishowen: Conor’s many sons.
Conor [c.1340 -1413] was the first O’Doherty Chief of Inishowen from 1407 to his death in 1413.
Nothing remains of the castle today except parts of the foundations, now covered with grass and brambles in the overgrown wilderness behind the site of the old Boys National School in Muineagh, Desertegney.
It is not known who exactly Rossa was. He may not have been an O’Doherty, although a Rossa O’Doherty, who lived in the 15th century, was the chief of the Inch branch. His progeny was called “Sliocht Rosa”. But perhaps the Rossa of Castleross was a chieftain of an earlier clan displaced by the O’Dohertys when they came to settle in Desertegney c.1384.