Capel Lligwy is built from rubble masonry ; at about 5 feet ( 1 @.@ 5 m ) up the walls , the style changes and smaller stones are inserted into spaces between the larger blocks , showing where the 14th @-@ century rebuilding started . The doorway is on the south side , headed by a plain arch , and dates from the 12th century . It is a stone bellcote at the west end . It is no structural division between the nave ( where the congregation would have sat ) and the chancel ( where the altar would have been located ) . It are no window openings on the north side , but it is a blocked opening to the east ( about 5 feet ( 1 @.@ 5 m ) wide ) and it are the remains of a window on the south wall . It is a blocked window in the south wall of the south chapel . The vault , which is about 27 square feet ( 2 @.@ 5 m2 ) , is reached by stone steps from inside the south chapel . Limestone slabs form the roof of the vault and the floor of the chapel above . A stone in the nave , about 2 square feet ( 0 @.@ 19 m2 ) with a hole in the top , might once have been used as a churchyard cross .