background Cornish cornwall England english eroded erosion geology gray Great Britain grey layers lines natural nature rock sedimentary silver texture worn bubble bubbles cold freeze frozen ice icy lake pebbles puddle rocks sveres water winter clouds colors grass green landscape light mountains outdoors sky space stones summer textures bridges hills railways shadows trains transport viaduct cliff coast contorted contours cyprus mediterranean mudstone shapes stone abstract architectural barrier basic brick-wall bricks brickwork coloring colouring colours constructed exterior external firm fitted large patchwork perspectives rock-wall rough rugged secure security shaped solid stonework strength strong style sunlight sunshine surface surfaces uneven variations various wall wallpaper well-built broken yellow animal arthropod Balanus barnacles hard Pembrokeshire wales welsh wild