Ancient towers, found chiefly in Ireland, of a tall, round, more or less tapering structure, divided into storeys, and with a conical top, erected in the neighbourhood of some church or monastery, and presumably of Christian origin, and probably used as strongholds in times of danger; of these there are 118 in Ireland, and three in Scotland—at Abernethy, Brechin, and Eglishay (Orkney).