Two 8th century granite grave slabs in the west side of the tower bear inscriptions that can still be read. One of them bears the name of Ardeachan, Abbot of Clonmacnoise. The abbey was attacked and destroyed by the English Elizabethan invaders and all its monks were slain. Later, during the Cromwellian conquest of Ireland, it is claimed in a book by Skeffington Gibbon (published in 1829) that Cromwellian troops, under the leadership of Colonel (or Major) Ormsby, 'immolated' (ie killed by fire) more than one hundred elderly clergy at Fuerty abbey.