Castle Donovan (Irish: Caisleán Uí Dhonnabháin) or Castledonovan or O'Donovan's Castle refer to the remains of the seat of the Clann Cathail. According to tradition, the tower was severely damaged by Oliver Cromwell's soldiers in the late 1640s, blown up with powder in retaliation for Donal III O'Donovan joining the Stuart side and for his involvement in the rebellion and massacres of 1641, and has been uninhabited since that time. It is now a listed National Monument.

 

According to legend, a constant drip of water eminates from the the ceiling of the ground floor chamber resulting from a dark deed many centuries ago. It is said that these are teardrops acting as a reminder of the cruel turn of events that took place in the rooms above.