angles blue blue-sky cables chains construction construction site construction work crane cranes danger height heights high hoist hoisting hook lifting metal power raising safety strength tall work working appearance background brick bricks brickwork build building building-blocks colors colours cracks firm loose perspectives rough selected selection singles solid surface surfaces texture textures variations variety walls abstract architectural architecture backdrop color colored colour coloured covered covering polished shaped shapes Sizes smooth smoothed stone tiled tiles varied wall wallpaper electric power electricity electricity poles electricity power lines energy equipment high voltage high voltage equipment house wiring insulators light power pole street light transformers wires wiring beams ceiling curved elements England english floors girders glass Great Britain iron London modern skyscraper steel strong structural structure struts symmetrical symmetry walkietalkie window art classic craft decorated decoration decorative fence handcraft handicraft ornament ornaments shape structures wrought iron wrought-iron wroughtiron bunch flowers gate old shade shadow sunlight confined display displayed heavy heavy-duty historical history machinery machines mobility powerful rails railway railway-yard restoration restoration-yard rust rusty trains transportation wheels