Fanning's Castle (Irish: Caisleán Uí Fhionáin), also called Whitamore's Castle,[1] is the remains of a tower house and National Monument[2] located in Limerick, Ireland.

[3] Fanning's Castle is located off Creagh Lane and Mary Street, opposite the tholsel,[4] on King's Island.

[7] The walls of the tower house are of roughly squared limestone blocks of varying sizes.

[8] The windows show ogee and mullions.

[9] The tower house incorporated a turret staircase and battlements.