seawall south of blackpool constructed of concrete honeycomb type structures with steps leading to the beach covered in tidal

architecture background bank barrier beach blackpool cement coast coastal coastline cobb concrete constructed covered defence defense defenses energy engineering erosion flood fylde grey harbor honeycomb landscape leading level made man ocean outdoors prevent promenade protect protection revetment sand sea seabee seawall seaweed shore south stairs steps stormy structures summer system tidal type vacation wall water waves