Drumharsna Castle is a five storey tower house known to have been owned by Shane Ballagh in 1577 but believed to have been built much earlier by the Kilkelly family.
Throughout the years, the castle survived the Cromwellian invasion and was still in use until the early 20th century. In 1920 however, the castle was occupied by the Black and Tans who caused extensive damage to the castle. The castle has been associated to stories of brutal murders by the Black and Tans. Both brothers, Patrick and Harry Loughnane, members of the Sinn Féin, political party were believed to have been taken to the castle before being shot to death in the nearby woods by the Black and Tans.
The castle now lies in ruins.