abstract appearance background coloring colors colouring colours contours contrast contrasts cracks fissures flaws gorge layered layers levels light lines natural pool ravine reflections rock rock-face rockface rocks rocky rough rugged shade shadows shape shapes steep stone stones strata stratum sunlight sunny sunshine surfaces texture textured textures walls water austere bare bleak canada cliff cold dangerous difficult environment extreme face forbidding freezing frozen glacier harsh high ice icy mountain mountainside nature Rockies Rocky Mountains severe silt snow stern angles backdrop backgrounds barrier blocks constructed fitted large limestone linear mortar perspective perspectives secure security solid stonework strength strong surface variations variety wall walled well-built colored coloured sandy shaped veins wallpaper brown ribbons shades of color shades of colour