 The tower house , or keep , at the west corner of the enclosure , measures 36 @.@ 5 feet ( 11 @.@ 1 m ) by 31 @.@ 5 feet ( 9 @.@ 6 m ) and originally had five storeys , although the roof and timber floors are now gone . The lowest level is a vaulted basement , with a vaulted kitchen above . The hall was on the next floor , with chambers above , all linked by a spiral stair . 
