abstract alphabet-A arrow concrete direction Dirt dirty discoloration discolored discolouration discoloured gray grey grooved grooves non-slip path pathway patterned paving raised rough Soil soiled surface surfaced surfaces texture textured textures uneven aged background brush stroke brushstroke brushstrokes grime grunge grungy paint painting weathered worn abundance angles appearance bricks colors colours firm lifted loose pavers paving-bricks perspectives plenty quantity rows sandy solid stacked stacks strength strong backdrop color colour metal rust rustic rusty hue hues series shade shades tone tones variations various