St Catherine's Island and Fort at foot of Castle beach with people walking around during the day

st catherine island fort castle beach people walking day tenby wales pembrokeshire tidal low tide waves ocean cloudy welsh napoleonic wars napoleon iii historical history zoo defense building sand coast coastal artillery seaside castle rock sherlock tourism touristic popular landmark travel handheld high angle rock landscape scenic scenery pembrokeshire coast national park shoreline welsh coast vacation leisure holiday beachgoers historic site