detail of a natural cave on the beach

adventure alga bay boulder calcareous cave cavern cavernous cliff coast cobble cobblestone cove crack crevice excursion excursionist fissure glare granite gravel gravelly grotto hole inlet limestone littoral marble nature opening outing pebble pebbly rock rocky sandy sea seaboard seafront seaside shore sightseer split stack stones stony sundrenched sunlit sunny sunshine tour venture water waterfront