Australia azure Bay of Islands blue coastline eroded erosion Great Ocean Road horizon landscape layers Natural landscape nature ocean rock sea sky stack terrain tide water water resources wave boulder carved coast coastal eerie form formation granite macabre mediterranean natural odd Sardinia strange unusual weird Cornish cornwall England english Great Britain rocks rocky sedimentary shore strata worn background blocks cracked geology gray grey texture yellow Balearic Islands boulders flutes green grow hard harsh majorca ridge sharp Spain trees wild wilderness algae beach cliff hillside Pembrokeshire sand seaweed united kingdom view wales welsh