beach cave cavern cliff coastline Cornish cornwall England english Great Britain hole natural nature ocean rock sand sea shore water waves cottage fisherman harbour hillside historical home house old rocks steps stone wall clifftop coast danger drop edge fun Gower holiday landscape leisure sheer steep tourism tourist vacation view wales cloud cold freezing icy mountains norway norwegian plateau road shadow sky snow snowy summer white wild ancient artificial bare.bleak barren desert dry escarpment harsh Israel Massada rocky roman sere siege slope algae chalk erode erosion face green kent low rockpool seaweed tide Birling Gap boulders cream eroded evening remnants Sussex